@phdthesis{MirskovaAdamovichMirskovetal.2013,
  author    = {Mirskova, Anna N. and Adamovich, Sergey N. and Mirskov, Rudolf G. and Schilde, Uwe},
  title     = {Reaction of pharmacological active tris-(2-hydroxyethyl) ammonium 4-chlorophenylsulfanylacetate with ZnCl2 or NiCl2: first conversion of a protic ionic liquid into metallated ionic liquid},
  doi       = {10.1186/1752-153X-7-34},
  year      = {2013},
  language  = {en}
}
@phdthesis{Men2013,
  author    = {Men, Yongjun},
  title     = {Poly(Ionic Liquid)-based thermoresponsive polymers and porous carbon materials},
  address   = {Potsdam},
  pages     = {101 S.},
  year      = {2013},
  language  = {en}
}
@phdthesis{Dominguez2013,
  author    = {Dom{\´i}nguez, Pablo Haro},
  title     = {Nanostructured poly(benzimidazole)s by chemical modification},
  address   = {Potsdam},
  pages     = {95, XXVIII S.},
  year      = {2013},
  language  = {en}
}
@phdthesis{Ast2013,
  author    = {Ast, Cindy},
  title     = {Design and photophysical characterization of single fluorophore-based ammonium sensors},
  address   = {Potsdam},
  pages     = {90 S.},
  year      = {2013},
  language  = {en}
}
@article{KramerKleinpeter2013,
  author    = {Kramer, Markus and Kleinpeter, Erich},
  title     = {A conformational study of N-acetyl glucosamine derivatives utilizing residual dipolar couplings},
  issn      = {1090-7807},
  year      = {2013},
  language  = {en}
}
@article{InalKoelschSelrieetal.2013,
  author    = {Inal, Sahika and K{\"o}lsch, Jonas D. and Selrie, Frank and Schenk, J{\"o}rg A. and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Neher, Dieter},
  title     = {A water soluble fluorescent polymer as a dual colour sensor for temperature and a specific protein},
  doi       = {10.1039/c3tb21245a},
  year      = {2013},
  abstract  = {We present two thermoresponsive water soluble copolymers prepared via free radical statistical copolymerization of N-isopropylacrylamide (NIPAm) and of oligo(ethylene glycol) methacrylates (OEGMAs), respectively, with a solvatochromic 7-(diethylamino)-3-carboxy-coumarin (DEAC)-functionalized monomer. In aqueous solutions, the NIPAm-based copolymer exhibits characteristic changes in its fluorescence profile in response to a change in solution temperature as well as to the presence of a specific protein, namely an anti-DEAC antibody. This polymer emits only weakly at low temperatures, but exhibits a marked fluorescence enhancement accompanied by a change in its emission colour when heated above its cloud point. Such drastic changes in the fluorescence and absorbance spectra are observed also upon injection of the anti-DEAC antibody, attributed to the specific binding of the antibody to DEAC moieties. Importantly, protein binding occurs exclusively when the polymer is in the well hydrated state below the cloud point, enabling a temperature control on the molecular recognition event. On the other hand, heating of the polymer-antibody complexes releases a fraction of the bound antibody. In the presence of the DEAC-functionalized monomer in this mixture, the released antibody competitively binds to the monomer and the antibody-free chains of the polymer undergo a more effective collapse and inter-aggregation. In contrast, the emission properties of the OEGMA-based analogous copolymer are rather insensitive to the thermally induced phase transition or to antibody binding. These opposite behaviours underline the need for a carefully tailored molecular design of responsive polymers aimed at specific applications, such as biosensing.},
  language  = {en}
}
@phdthesis{Thuermer2013,
  author    = {Th{\"u}rmer, Stephan},
  title     = {Inquiring photoelectrons about the dynamics in liquid water},
  publisher = {Mensch \& Buch Verl.},
  address   = {Berlin},
  isbn      = {978-3-86387-336-3},
  pages     = {X, 106 S.},
  year      = {2013},
  language  = {en}
}
@phdthesis{Rohrmann2013,
  author    = {Rohrmann, Johannes},
  title     = {The transcription factors orchestra of ripening tomato fruits},
  address   = {Potsdam},
  pages     = {Ix, 136 S. + 1 CD-Rom},
  year      = {2013},
  language  = {en}
}
@phdthesis{Krannig2013,
  author    = {Krannig, Kai-Steffen},
  title     = {Smart biohybrid polymers : synthesis and structures of novel glycopolypeptides},
  address   = {Potsdam},
  pages     = {165 S.},
  year      = {2013},
  language  = {en}
}
@phdthesis{Soll2013,
  author    = {Soll, Sebastian},
  title     = {Structural properties and functional materials of Vinylimidazolium-type Poly(Ionic Liquid)s},
  address   = {Potsdam},
  pages     = {127 S.},
  year      = {2013},
  language  = {en}
}
@phdthesis{Tomczyk2013,
  author    = {Tomczyk, Jaroslaw},
  title     = {Photoinduced optical anisotropy in films of photochromic star-shaped liquid crystals},
  address   = {Potsdam},
  pages     = {121 S.},
  year      = {2013},
  language  = {en}
}
@article{LiBabuTurneretal.2013,
  author    = {Li, Hongguang and Babu, Sukumaran Santhosh and Turner, Sarah T. and Neher, Dieter and Hollamby, Martin J. and Tomohito, Seki and Yagai, Shiki and deguchi, Yonekazu and M{\"o}hwald, Helmuth and Nakanishi, Takashi},
  title     = {Alkylated-C60 based soft materials: regulation of self-assembly and optoelectronic properties by chain branching},
  doi       = {10.1039/C3TC00066D},
  year      = {2013},
  abstract  = {Derivatization of fullerene (C60) with branched aliphatic chains softens C60-based materials and enables the formation of thermotropic liquid crystals and room temperature nonvolatile liquids. This work demonstrates that by carefully tuning parameters such as type, number and substituent position of the branched chains, liquid crystalline C60 materials with mesophase temperatures suited for photovoltaic cell fabrication and room temperature nonvolatile liquid fullerenes with tunable viscosity can be obtained. In particular, compound 1, with branched chains, exhibits a smectic liquid crystalline phase extending from 84°C to room temperature. Analysis of bulk heterojunction (BHJ) organic solar cells with a ca. 100 nm active layer of compound 1 and poly(3-hexylthiophene) (P3HT) as an electron acceptor and an electron donor, respectively, reveals an improved performance (power conversion efficiency, PCE: 1.6 {\~n} 0.1\%) in comparison with another compound, 10 (PCE: 0.5 {\~n} 0.1\%). The latter, in contrast to 1, carries linear aliphatic chains and thus forms a highly ordered solid lamellar phase at room temperature. The solar cell performance of 1 blended with P3HT approaches that of PCBM/P3HT for the same active layer thickness. This indicates that C60 derivatives bearing branched tails are a promising class of electron acceptors in soft (flexible) photovoltaic devices.},
  language  = {en}
}
@phdthesis{Yu2013,
  author    = {Yu, Linghui},
  title     = {Hydrothermal synthesis of carbon and carbon nanocomposite materials for environmental and energy applications},
  address   = {Potsdam},
  pages     = {103 S.},
  year      = {2013},
  language  = {en}
}
@article{TheteRojasNeumeyeretal.2013,
  author    = {Thete, Aniket and Rojas, Oscar and Neumeyer, David and Koetz, Joachim and Dujardin, Erik},
  title     = {Ionic liquid-assisted morphosynthesis of gold nanorods using polyethyleneimine-capped seeds},
  doi       = {10.1039/C3RA22112A},
  year      = {2013},
  abstract  = {Seed-mediated gold nanorods with tunable lengths are prepared using new polyethyleneimine-capped gold nanoparticles synthesized in ionic liquid. The effect of polyethyleneimine and ionic liquid during nanorod growth is investigated and shows a marked effect on their final aspect ratio.},
  language  = {en}
}
@misc{InalKoelschChiappisietal.2013,
  author    = {Inal, Sahika and K{\"o}lsch, Jonas D. and Chiappisi, Leonardo and Janietz, Dietmar and Gradzielski, Michael and Laschewsky, Andr{\´e} and Neher, Dieter},
  title     = {Structure-related differences in the temperature-regulated fluorescence response of LCST type polymers},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95379},
  pages     = {6603 -- 6612},
  year      = {2013},
  abstract  = {We demonstrate new fluorophore-labelled materials based on acrylamide and on oligo(ethylene glycol) (OEG) bearing thermoresponsive polymers for sensing purposes and investigate their thermally induced solubility transitions. It is found that the emission properties of the polarity-sensitive (solvatochromic) naphthalimide derivative attached to three different thermoresponsive polymers are highly specific to the exact chemical structure of the macromolecule. While the dye emits very weakly below the LCST when incorporated into poly(N-isopropylacrylamide) (pNIPAm) or into a polyacrylate backbone bearing only short OEG side chains, it is strongly emissive in polymethacrylates with longer OEG side chains. Heating of the aqueous solutions above their cloud point provokes an abrupt increase of the fluorescence intensity of the labelled pNIPAm, whereas the emission properties of the dye are rather unaffected as OEG-based polyacrylates and methacrylates undergo phase transition. Correlated with laser light scattering studies, these findings are ascribed to the different degrees of pre-aggregation of the chains at low temperatures and to the extent of dehydration that the phase transition evokes. It is concluded that although the temperature-triggered changes in the macroscopic absorption characteristics, related to large-scale alterations of the polymer chain conformation and aggregation, are well detectable and similar for these LCST-type polymers, the micro-environment provided to the dye within each polymer network differs substantially. Considering sensing applications, this finding is of great importance since the temperature-regulated fluorescence response of the polymer depends more on the macromolecular architecture than the type of reporter fluorophore.},
  language  = {en}
}
@misc{LiBabuTurneretal.2013,
  author    = {Li, Hongguang and Babu, Sukumaran Santhosh and Turner, Sarah T. and Neher, Dieter and Hollamby, Martin J. and Seki, Tomohiro and Yagai, Shiki and Deguchi, Yonekazu and M{\"o}hwald, Helmuth and Nakanishi, Takashi},
  title     = {Alkylated-C60 based soft materials},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95358},
  pages     = {1943 -- 1951},
  year      = {2013},
  abstract  = {Derivatization of fullerene (C60) with branched aliphatic chains softens C60-based materials and enables the formation of thermotropic liquid crystals and room temperature nonvolatile liquids. This work demonstrates that by carefully tuning parameters such as type, number and substituent position of the branched chains, liquid crystalline C60 materials with mesophase temperatures suited for photovoltaic cell fabrication and room temperature nonvolatile liquid fullerenes with tunable viscosity can be obtained. In particular, compound 1, with branched chains, exhibits a smectic liquid crystalline phase extending from 84 °C to room temperature. Analysis of bulk heterojunction (BHJ) organic solar cells with a ca. 100 nm active layer of compound 1 and poly(3-hexylthiophene) (P3HT) as an electron acceptor and an electron donor, respectively, reveals an improved performance (power conversion efficiency, PCE: 1.6 ± 0.1\%) in comparison with another compound, 10 (PCE: 0.5 ± 0.1\%). The latter, in contrast to 1, carries linear aliphatic chains and thus forms a highly ordered solid lamellar phase at room temperature. The solar cell performance of 1 blended with P3HT approaches that of PCBM/P3HT for the same active layer thickness. This indicates that C60 derivatives bearing branched tails are a promising class of electron acceptors in soft (flexible) photovoltaic devices.},
  language  = {en}
}
@misc{InalKoelschSellrieetal.2013,
  author    = {Inal, Sahika and K{\"o}lsch, Jonas D. and Sellrie, Frank and Schenk, J{\"o}rg A. and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Neher, Dieter},
  title     = {A water soluble fluorescent polymer as a dual colour sensor for temperature and a specific protein},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95336},
  pages     = {6373 -- 6381},
  year      = {2013},
  abstract  = {We present two thermoresponsive water soluble copolymers prepared via free radical statistical copolymerization of N-isopropylacrylamide (NIPAm) and of oligo(ethylene glycol) methacrylates (OEGMAs), respectively, with a solvatochromic 7-(diethylamino)-3-carboxy-coumarin (DEAC)- functionalized monomer. In aqueous solutions, the NIPAm-based copolymer exhibits characteristic changes in its fluorescence profile in response to a change in solution temperature as well as to the presence of a specific protein, namely an anti-DEAC antibody. This polymer emits only weakly at low temperatures, but exhibits a marked fluorescence enhancement accompanied by a change in its emission colour when heated above its cloud point. Such drastic changes in the fluorescence and absorbance spectra are observed also upon injection of the anti-DEAC antibody, attributed to the specific binding of the antibody to DEAC moieties. Importantly, protein binding occurs exclusively when the polymer is in the well hydrated state below the cloud point, enabling a temperature control on the molecular recognition event. On the other hand, heating of the polymer-antibody complexes releases a fraction of the bound antibody. In the presence of the DEAC-functionalized monomer in this mixture, the released antibody competitively binds to the monomer and the antibody-free chains of the polymer undergo a more effective collapse and inter-aggregation. In contrast, the emission properties of the OEGMA-based analogous copolymer are rather insensitive to the thermally induced phase transition or to antibody binding. These opposite behaviours underline the need for a carefully tailored molecular design of responsive polymers aimed at specific applications, such as biosensing.},
  language  = {en}
}
@misc{MenSiebenbuergerQiuetal.2013,
  author    = {Men, Yongjun and Siebenb{\"u}rger, Miriam and Qiu, Xunlin and Antonietti, Markus and Yuan, Jiayin},
  title     = {Low fractions of ionic liquid or poly(ionic liquid) can activate polysaccharide biomass into shaped, flexible and fire-retardant porous carbons},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95250},
  pages     = {11887 -- 11887},
  year      = {2013},
  abstract  = {Sugar-based molecules and polysaccharide biomass can be turned into porous functional carbonaceous products at comparably low temperatures of 400 °C under a nitrogen atmosphere in the presence of an ionic liquid (IL) or a poly(ionic liquid) (PIL). The IL and PIL act as "activation agents" with own structural contribution, and effectively promote the conversion and pore generation in the biomaterials even at a rather low doping ratio (7 wt\%). In addition, this "induced carbonization" and pore forming phenomenon enables the preservation of the biotemplate shape to the highest extent and was employed to fabricate shaped porous carbonaceous materials from carbohydrate-based biotemplates, exemplified here with cellulose filter membranes, coffee filter paper and natural cotton. These carbonized hybrids exhibit comparably good mechanical properties, such as bendability of membranes or shape recovery of foams. Moreover, the nitrogen atoms incorporated in the final products from the IL/PIL precursors further improve the oxidation stability in the fire-retardant tests.},
  language  = {en}
}
@misc{DiFlorioBruendermannYadavallietal.2013,
  author    = {Di Florio, Giuseppe and Br{\"u}ndermann, Erik and Yadavalli, Nataraja Sekhar and Santer, Svetlana and Havenith, Martina},
  title     = {Polarized 3D Raman and nanoscale near-field optical microscopy of optically inscribed surface relief gratings},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95233},
  pages     = {1544 -- 1554},
  year      = {2013},
  abstract  = {We have used polarized confocal Raman microspectroscopy and scanning near-field optical microscopy with a resolution of 60 nm to characterize photoinscribed grating structures of azobenzene doped polymer films on a glass support. Polarized Raman microscopy allowed determining the reorientation of the chromophores as a function of the grating phase and penetration depth of the inscribing laser in three dimensions. We found periodic patterns, which are not restricted to the surface alone, but appear also well below the surface in the bulk of the material. Near-field optical microscopy with nanoscale resolution revealed lateral two-dimensional optical contrast, which is not observable by atomic force and Raman microscopy.},
  language  = {en}
}
@misc{McQuadeO'BrienDoerretal.2013,
  author    = {McQuade, D. Tyler and O'Brien, Alexander G. and D{\"o}rr, Markus and Rajaratnam, Rajathees and Eisold, Ursula and Monnanda, Bopanna and Nobuta, Tomoya and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Meggers, Eric and Seeberger, Peter H.},
  title     = {Continuous synthesis of pyridocarbazoles and initial photophysical and bioprobe characterization},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95214},
  pages     = {4067 -- 4070},
  year      = {2013},
  abstract  = {Pyridocarbazoles when ligated to transition metals yield high affinity kinase inhibitors. While batch photocyclizations enable the synthesis of these heterocycles, the non-oxidative Mallory reaction only provides modest yields and difficult to purify mixtures. We demonstrate here that a flow-based Mallory cyclization provides superior results and enables observation of a clear isobestic point. The flow method allowed us to rapidly synthesize ten pyridocarbazoles and for the first time to document their interesting photophysical attributes. Preliminary characterization reveals that these molecules might be a new class of fluorescent bioprobe.},
  language  = {en}
}
@misc{TheteRojasNeumeyeretal.2013,
  author    = {Thete, Aniket and Rojas, Oscar and Neumeyer, David and Koetz, Joachim and Dujardin, Erik},
  title     = {Ionic liquid-assisted morphosynthesis of gold nanorods using polyethyleneimine-capped seeds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95196},
  pages     = {14294 -- 14298},
  year      = {2013},
  abstract  = {Seed-mediated gold nanorods with tunable lengths are prepared using new polyethyleneimine-capped gold nanoparticles synthesized in ionic liquid. The effect of polyethyleneimine and ionic liquid during nanorod growth is investigated and shows a marked effect on their final aspect ratio.},
  language  = {en}
}
@misc{JungingerKuebelSchacheretal.2013,
  author    = {Junginger, Mathias and K{\"u}bel, Christian and Schacher, Felix H. and M{\"u}ller, Axel H. E. and Taubert, Andreas},
  title     = {Crystal structure and chemical composition of biomimetic calcium phosphate nanofibers},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95176},
  pages     = {11301 -- 11308},
  year      = {2013},
  abstract  = {Calcium phosphate nanofibers with a diameter of only a few nanometers and a cotton-ball-like aggregate morphology have been reported several times in the literature. Although fiber formation seems reproducible in a variety of conditions, the crystal structure and chemical composition of the fibers have been elusive. Using scanning transmission electron microscopy, low dose electron (nano)diffraction, energy-dispersive X-ray spectroscopy, and energy-filtered transmission electron microscopy, we have assigned crystal structures and chemical compositions to the fibers. Moreover, we demonstrate that the mineralization process yields true polymer/calcium phosphate hybrid materials where the block copolymer template is closely associated with the calcium phosphate.},
  language  = {en}
}
@misc{ThielZehbeRoeseretal.2013,
  author    = {Thiel, Kerstin and Zehbe, Rolf and Roeser, Jer{\^o}m{\´e} and Strauch, Peter and Enthaler, Stephan and Thomas, Arne},
  title     = {A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95118},
  pages     = {1848 -- 1856},
  year      = {2013},
  abstract  = {A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.},
  language  = {en}
}
@misc{SchmidtElizarovBergeretal.2013,
  author    = {Schmidt, Bernd and Elizarov, Nelli and Berger, Ren{\´e} and H{\"o}lter, Frank},
  title     = {Scope and limitations of the Heck-Matsuda-coupling of phenol diazonium salts and styrenes},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95070},
  pages     = {3674 -- 3691},
  year      = {2013},
  abstract  = {4-Phenol diazonium salts undergo Pd-catalyzed Heck reactions with various styrenes to 4'-hydroxy stilbenes. In almost all cases higher yields and fewer side products were observed, compared to the analogous 4-methoxy benzene diazonium salts. In contrast, the reaction fails completely with 2- and 3-phenol diazonium salts. For these substitution patterns the methoxy-substituted derivatives are superior.},
  language  = {en}
}
@misc{SchmidtHauke2013,
  author    = {Schmidt, Bernd and Hauke, Sylvia},
  title     = {Cross metathesis of allyl alcohols},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95037},
  pages     = {4194 -- 4206},
  year      = {2013},
  abstract  = {Under standard conditions the cross metathesis of allyl alcohols and methyl acrylate is accompanied by the formation of ketones, resulting from uncontrolled and undesired double bond isomerization. By conducting the CM in the presence of phenol, the catalyst loading and the reaction time required for quantiative conversion can be reduced, and isomerization can be suppressed. On the other hand, consecutive isomerization can be deliberately promoted by evaporating excess methyl acrylate after completing cross metathesis and by adding a base or silane as chemical triggers.},
  language  = {en}
}
@misc{WinterThielZabeletal.2013,
  author    = {Winter, Alette and Thiel, Kerstin and Zabel, Andr{\´e} and Klamroth, Tillmann and P{\"o}ppl, Andreas and Kelling, Alexandra and Schilde, Uwe and Taubert, Andreas and Strauch, Peter},
  title     = {Tetrahalidocuprates(II) - structure and EPR spectroscopy},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95012},
  pages     = {1019 -- 1030},
  year      = {2013},
  abstract  = {We present and discuss the results of crystallographic and electron paramagnetic resonance (EPR) spectroscopic analyses of five tetrachloridocuprate(II) complexes to supply a useful tool for the structural characterisation of the [CuCl4]2- moiety in the liquid state, for example in ionic liquids, or in solution. Bis(benzyltriethylammonium)-, bis(trimethylphenylammonium)-, bis(ethyltriphenylphosphonium)-, bis(benzyltriphenylphosphonium)-, and bis(tetraphenylarsonium)tetrachloridocuprate(II) were synthesised and characterised by elemental, IR, EPR and X-ray analyses. The results of the crystallographic analyses show distorted tetrahedral coordination geometry of all [CuCl4]2- anions in the five complexes and prove that all investigated complexes are stabilised by hydrogen bonds of different intensities. Despite the use of sterically demanding ammonium, phosphonium and arsonium cations to obtain the separation of the paramagnetic Cu(II) centres for EPR spectroscopy no hyperfine structure was observed in the EPR spectra but the principal values of the electron Zeeman tensor, g∥ and g⊥, could be determined. With these EPR data and the crystallographic parameters we were able to carry out a correlation study to anticipate the structural situation of tetrachloridocuprates in different physical states. This correlation is in good agreement with DFT calculations.},
  language  = {en}
}
@misc{SchoenbornHartke2013,
  author    = {Sch{\"o}nborn, Jan Boyke and Hartke, Bernd},
  title     = {Photochemical dynamics of E-methylfurylfulgide},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94516},
  pages     = {2483 -- 2490},
  year      = {2013},
  abstract  = {With the present theoretical study of the photochemical switching of E-methylfurylfulgide we contribute an important step towards the understanding of the photochemical processes in furylfulgide-related molecules. We have carried out large-scale, full-dimensional direct semiempirical configuration-interaction surface-hopping dynamics of the photoinduced ring-closure reaction. Simulated static and dynamical UV/Vis-spectra show good agreement with experimental data of the same molecule. By a careful investigation of our dynamical data, we were able to identify marked differences to the dynamics of the previously studied E-isopropylfurylfulgide. With our simulations we can not only reproduce the experimentally observed quantum yield differences qualitatively but we can also pinpoint two reasons for them: kinematics and pre-orientation. With our analysis, we thus offer straightforward molecular explanations for the high sensitivity of the photodynamics towards seemingly minor changes in molecular constitution. Beyond the realm of furylfulgides, these insights provide additional guidance to the rational design of photochemically switchable molecules.},
  language  = {en}
}
@misc{BanerjeeSaalfrank2013,
  author    = {Banerjee, Shiladitya and Saalfrank, Peter},
  title     = {Vibrationally resolved absorption, emission and resonance Raman spectra of diamondoids},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94542},
  pages     = {144 -- 158},
  year      = {2013},
  abstract  = {The time-dependent approach to electronic spectroscopy, as popularized by Heller and coworkers in the 1980's, is applied here in conjunction with linear-response, time-dependent density functional theory to study vibronic absorption, emission and resonance Raman spectra of several diamondoids. Two-state models, the harmonic and the Condon approximations, are used for the calculations, making them easily applicable to larger molecules. The method is applied to nine pristine lower and higher diamondoids: adamantane, diamantane, triamantane, and three isomers each of tetramantane and pentamantane. We also consider a hybrid species "Dia = Dia" - a shorthand notation for a recently synthesized molecule comprising two diamantane units connected by a C[double bond, length as m-dash]C double bond. We resolve and interpret trends in optical and vibrational properties of these molecules as a function of their size, shape, and symmetry, as well as effects of "blending" with sp2-hybridized C-atoms. Time-dependent correlation functions facilitate the computations and shed light on the vibrational dynamics following electronic transitions.},
  language  = {en}
}
@misc{CherstvyMetzler2013,
  author    = {Cherstvy, Andrey G. and Metzler, Ralf},
  title     = {Population splitting, trapping, and non-ergodicity in heterogeneous diffusion processes},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94468},
  pages     = {20220 -- 20235},
  year      = {2013},
  abstract  = {We consider diffusion processes with a spatially varying diffusivity giving rise to anomalous diffusion. Such heterogeneous diffusion processes are analysed for the cases of exponential, power-law, and logarithmic dependencies of the diffusion coefficient on the particle position. Combining analytical approaches with stochastic simulations, we show that the functional form of the space-dependent diffusion coefficient and the initial conditions of the diffusing particles are vital for their statistical and ergodic properties. In all three cases a weak ergodicity breaking between the time and ensemble averaged mean squared displacements is observed. We also demonstrate a population splitting of the time averaged traces into fast and slow diffusers for the case of exponential variation of the diffusivity as well as a particle trapping in the case of the logarithmic diffusivity. Our analysis is complemented by the quantitative study of the space coverage, the diffusive spreading of the probability density, as well as the survival probability.},
  language  = {en}
}
@misc{MondalBhuniaDemeshkoetal.2013,
  author    = {Mondal, Suvendu Sekhar and Bhunia, Asamanjoy and Demeshko, Serhiy and Kelling, Alexandra and Schilde, Uwe and Janiak, Christoph and Holdt, Hans-J{\"u}rgen},
  title     = {Synthesis of a Co(II)-imidazolate framework from an anionic linker precursor},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94424},
  pages     = {39 -- 42},
  year      = {2013},
  abstract  = {A Co(II)-imidazolate-4-amide-5-imidate based MOF, IFP-5, is synthesized by using an imidazolate anion-based novel ionic liquid as a linker precursor under solvothermal conditions. IFP-5 shows significant amounts of gas (N2, CO2, CH4 and H2) uptake capacities. IFP-5 exhibits an independent high spin Co(II) centre and antiferromagnetic coupling.},
  language  = {en}
}
@misc{MondalDeyBaburinetal.2013,
  author    = {Mondal, Suvendu Sekhar and Dey, Subarna and Baburin, Igor A. and Kelling, Alexandra and Schilde, Uwe and Seifert, Gotthard and Janiak, Christoph and Holdt, Hans-J{\"u}rgen},
  title     = {Syntheses of two imidazolate-4-amide-5-imidate linker-based hexagonal metal-organic frameworks with flexible ethoxy substituent},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94360},
  pages     = {9394 -- 9399},
  year      = {2013},
  abstract  = {A rare example of in situ linker generation with the formation of soft porous Zn- and Co-MOFs (IFP-9 and -10, respectively) is reported. The flexible ethoxy groups of IFP-9 and -10 protrude into the 1D hexagonal channels. The gas-sorption behavior of both materials for H2, CO2 and CH4 showed wide hysteretic isotherms, typical for MOFs having a flexible substituent which can give rise to a gate effect.},
  language  = {en}
}
@misc{MondalBhuniaBaburinetal.2013,
  author    = {Mondal, Suvendu Sekhar and Bhunia, Asamanjoy and Baburin, Igor A. and J{\"a}ger, Christian and Kelling, Alexandra and Schilde, Uwe and Seifert, Gotthard and Janiak, Christoph and Holdt, Hans-J{\"u}rgen},
  title     = {Gate effects in a hexagonal zinc-imidazolate-4-amide-5-imidate framework with flexible methoxy substituents and CO2 selectivity},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94341},
  pages     = {7599 -- 7601},
  year      = {2013},
  abstract  = {A new imidazolate-4-amide-5-imidate based MOF, IFP-7, is generated, having flexible methoxy groups, which act as molecular gates for guest molecules. This allows highly selective CO2 sorption over N2 and CH4 gases.},
  language  = {en}
}
@phdthesis{Kroener2013,
  author    = {Kr{\"o}ner, Dominik},
  title     = {Analysis and control of light-induced processes in molecules: Electron and nuclear quantum dynamics for aspects of stereoisomerism and spectroscopy},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-70477},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {The habilitation thesis covers theoretical investigations on light-induced processes in molecules. The study is focussed on changes of the molecular electronic structure and geometry, caused either by photoexcitation in the event of a spectroscopic analysis, or by a selective control with shaped laser pulses. The applied and developed methods are predominantly based on quantum chemistry as well as on electron and nuclear quantum dynamics, and in parts on molecular dynamics. The studied scientific problems deal with stereoisomerism and the question of how to either switch or distinguish chiral molecules using laser pulses, and with the essentials for the simulation of the spectroscopic response of biochromophores, in order to unravel their photophysics. The accomplished findings not only explain experimental results and extend existing approaches, but also contribute significantly to the basic understanding of the investigated light-driven molecular processes. The main achievements can be divided in three parts: First, a quantum theory for an enantio- and diastereoselective or, in general, stereoselective laser pulse control was developed and successfully applied to influence the chirality of molecular switches. The proposed axially chiral molecules possess different numbers of "switchable" stable chiral conformations, with one particular switch featuring even a true achiral "off"-state which allows to enantioselectively "turn on" its chirality. Furthermore, surface mounted chiral molecular switches with several well-defined orientations were treated, where a newly devised highly flexible stochastic pulse optimization technique provides high stereoselectivity and efficiency at the same time, even for coupled chirality-changing degrees of freedom. Despite the model character of these studies, the proposed types of chiral molecular switches and, all the more, the developed basic concepts are generally applicable to design laser pulse controlled catalysts for asymmetric synthesis, or to achieve selective changes in the chirality of liquid crystals or in chiroptical nanodevices, implementable in information processing or as data storage. Second, laser-driven electron wavepacket dynamics based on ab initio calculations, namely time-dependent configuration interaction, was extended by the explicit inclusion of magnetic field-magnetic dipole interactions for the simulation of the qualitative and quantitative distinction of enantiomers in mass spectrometry by means of circularly polarized ultrashort laser pulses. The developed approach not only allows to explain the origin of the experimentally observed influence of the pulse duration on the detected circular dichroism in the ion yield, but also to predict laser pulse parameters for an optimal distinction of enantiomers by ultrashort shaped laser pulses. Moreover, these investigations in combination with the previous ones provide a fundamental understanding of the relevance of electric and magnetic interactions between linearly or non-linearly polarized laser pulses and (pro-)chiral molecules for either control by enantioselective excitation or distinction by enantiospecific excitation. Third, for selected light-sensitive biological systems of central importance, like e.g. antenna complexes of photosynthesis, simulations of processes which take place during and after photoexcitation of their chromophores were performed, in order to explain experimental (spectroscopic) findings as well as to understand the underlying photophysical and photochemical principles. In particular, aspects of normal mode mixing due to geometrical changes upon photoexcitation and their impact on (time-dependent) vibronic and resonance Raman spectra, as well as on intramolecular energy redistribution were addressed. In order to explain unresolved experimental findings, a simulation program for the calculation of vibronic and resonance Raman spectra, accounting for changes in both vibrational frequencies and normal modes, was created based on a time-dependent formalism. In addition, the influence of the biochemical environment on the electronic structure of the chromophores was studied by electrostatic interactions and mechanical embedding using hybrid quantum-classical methods. Environmental effects were found to be of importance, in particular, for the excitonic coupling of chromophores in light-harvesting complex II. Although the simulations for such highly complex systems are still restricted by various approximations, the improved approaches and obtained results have proven to be important contributions for a better understanding of light-induced processes in biosystems which also adds to efforts of their artificial reproduction.},
  language  = {en}
}
@phdthesis{Suetterlin2013,
  author    = {S{\"u}tterlin, Martin},
  title     = {New inverse hydogel opals as protein responsive sensors},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-70179},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {In this work, the development of temperature- and protein-responsive sensor materials based on biocompatible, inverse hydrogel opals (IHOs) is presented. With these materials, large biomolecules can be specifically recognised and the binding event visualised. The preparation of the IHOs was performed with a template process, for which monodisperse silica particles were vertically deposited onto glass slides as the first step. The obtained colloidal crystals with a thickness of 5 μm displayed opalescent reflections because of the uniform alignment of the colloids. As a second step, the template was embedded in a matrix consisting of biocompatible, thermoresponsive hydrogels. The comonomers were selected from the family of oligo(ethylene glycol)methacrylates. The monomer solution was injected into a polymerisation mould, which contained the colloidal crystals as a template. The space in-between the template particles was filled with the monomer solution and the hydrogel was cured via UV-polymerisation. The particles were chemically etched, which resulted in a porous inner structure. The uniform alignment of the pores and therefore the opalescent reflection were maintained, so these system were denoted as inverse hydrogel opals. A pore diameter of several hundred nanometres as well as interconnections between the pores should facilitate a diffusion of bigger (bio)molecules, which was always a challenge in the presented systems until now. The copolymer composition was chosen to result in a hydrogel collapse over 35 °C. All hydrogels showed pronounced swelling in water below the critical temperature. The incorporation of a reactive monomer with hydroxyl groups ensured a potential coupling group for the introduction of recognition units for analytes, e.g. proteins. As a test system, biotin as a recognition unit for avidin was coupled to the IHO via polymer-analogous Steglich esterification. The amount of accessible biotin was quantified with a colorimetric binding assay. When avidin was added to the biotinylated IHO, the wavelength of the opalescent reflection was significantly shifted and therefore the binding event was visualised. This effect is based on the change in swelling behaviour of the hydrogel after binding of the hydrophilic avidin, which is amplified by the thermoresponsive nature of the hydrogel. A swelling or shrinking of the pores induces a change in distance of the crystal planes, which are responsible for the colour of the reflection. With these findings, the possibility of creating sensor materials or additional biomolecules in the size range of avidin is given.},
  language  = {en}
}
@phdthesis{Chung2013,
  author    = {Chung, Kang Ko},
  title     = {Heteroatom-containing carbons for high energy density supercapacitor},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-69826},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {The supercapacitor is one of the most important energy storage devices as its construction allows for addressing many of the drawbacks related to batteries, but the low energy density of current systems is a major issue. In this doctoral dissertation, with a view to attaining high energy density supercapacitor systems that can be comparable to those for batteries, new heteroatom-containing carbons in the form of particles and three-dimensional films were investigated. A nitrogen-containing material, acrodam, was chosen as the carbon precursor due to the inexpensiveness, high carbonization yield, oligomerizability, etc. The carbon particles were prepared from acrodam together with caesium acetate as a meltable flux agent, and disclosed excellent properties in hydroquinone-loaded sulphuric acid electrolyte with high energy densities (up to 133.0 Wh kg-1) and sufficient cycle stabilities. These properties are already now comparable to those of batteries. Besides, conductive carbon three-dimensional films were fabricated using acrodam oligomer as the precursor by the inexpensive spin coating method. The films were found to be homogeneous, flat, void- and crack-free, and high conductivities (up to 334 S cm-1) could be obtained at the carbonization temperature of 1000 ºC. Furthermore, a porous carbon three-dimensional film could be formed using an organic template at the first attempt. This finding demonstrates the film's potentiality for various applications such as supercapacitor electrode; the essential absence of contact resistance within the network should contribute to effective transportation of electron within the electrode. The progress made in this dissertation will open a new way to further enhancement of energy density for supercapacitor as well as other applications that exceeds the current properties.},
  language  = {en}
}
@misc{Metzke2013,
  type      = {Master Thesis},
  author    = {Metzke, Sarah},
  title     = {Synthesis and characterization of transition metal nitrides and carbides for catalysis and electrochemistry application},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-69835},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {It was the goal of this work to explore two different synthesis pathways using green chemistry. The first part of this thesis is focusing on the use of the urea-glass route towards single phase manganese nitride and manganese nitride/oxide nano-composites embedded in carbon, while the second part of the thesis is focusing on the use of the "saccharide route" (namely cellulose, sucrose, glucose and lignin) towards metal (Ni0), metal alloy (Pd0.9Ni0.1, Pd0.5Ni0.5, Fe0.5Ni0.5, Cu0.5Ni0.5 and W0.15Ni0.85) and ternary carbide (Mn0.75Fe2.25C) nanoparticles embedded in carbon. In the interest of battery application, MnN0.43 nanoparticles surrounded by a graphitic shell and embedded in carbon with a high surface area (79 m^2/g) were synthesized, following a previously set route.The comparison of the material characteristics before and after the discharge showed no remarkable difference in terms of composition and just slight differences in the morphological point of view, meaning the particles are stable but agglomerate. The graphitic shell is contributing to the resistance of the material and leads to a fine cyclic stability over 140 cycles of 230 mAh/g after the first charge/discharge and coulombic efficiencies close to 100\%. Due to the low voltage towards Li/Li+ and the low polarization, it might be an attractive anode material for lithium ion batteries. However, the capacity is still noticeably lower than the theoretical value for MnN0.43. A mixture of MnN0.43 and MnO nanoparticles embedded in carbon (surface area 93 m^2/g) was able to improve the cyclic stability to over 160 cycles giving a capacity of 811 mAh/g, which is considerably higher than the capacity of the conventional material graphite (372 mAh/g). This nano-composite seems to agglomerate less during the process of discharge. Interestingly, although the capacity is much higher than of the single phase manganese nitride, the nano-composite seems to only contain MnN0.43 nanoparticles after the process of discharge with no oxide phase to be found. Concerning catalysis application, different metal, metal alloy, and metal carbide nanoparticles were synthesized using the saccharide route. At first, systems that were already investigated before, being Pd0.9Ni0.1, Pd0.5Ni0.5, Fe0.5Ni0.5 and Mn0.75Fe2.25C using cellulose as the carbon source were prepared and tested in an alkylation reaction of toluene with benzylchloride. Unexpectedly, the metal alloys did not show any catalytic activity, but the ternary carbide Mn0.75Fe2.25C showed fine catalytic activity of 98\% conversion after 9 hour reaction time (110 °C). In a second step, the saccharide route was modified towards other carbon sources and carbon to metal ratios in order to improve the homogeneity of the samples and accessibility of the particle surfaces. The used carbon sources sucrose and glucose are similar in their basic structure of carbohydrates, but reducing the (polymeric) chain length. Indeed, the cellulose could be successfully replaced by sucrose and glucose. A lower carbon to metal ratio was found to influence the size, homogeneity and accessibility (as evidenced by TEM) of the samples. Since sucrose is an aliment, glucose is the better choice as a carbon source. Using glucose, the synthesis of Cu0.5Ni0.5 and W0.15Ni0.85 nano-composites was also possible, although the later was never obtained as pure phase. These alloy nano-composites were tested, along with nickel0 nanoparticles also prepared with glucose and on their catalytic activity towards the reduction of phenylacetylene. The results obtained let believe that any (poly) saccharide, including lignin, could be used as carbon source. The nickel0 nano-composites prepared with lignin as a carbon source were tested along with those prepared with cellulose and sucrose for their catalytic activity in the transfer hydrogenation of nitrobenzene (results compared with exposed nickel nanoparticles and nickel supported on carbon) leading to very promising results. Based on the urea-glass route and the saccharide route, simple equipment and transition metals, it was possible to have a one-pot synthesize with scale-up possibilities towards new material that can be applied in catalysis and battery systems.},
  language  = {en}
}
@phdthesis{Santan2013,
  author    = {Santan, Harshal Diliprao},
  title     = {Synthesis and characterization of thermosensitive hydrogels derived from polysaccharides},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-69793},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {In this work, thermosensitive hydrogels having tunable thermo-mechanical properties were synthesized. Generally the thermal transition of thermosensitive hydrogels is based on either a lower critical solution temperature (LCST) or critical micelle concentration/ temperature (CMC/ CMT). The temperature dependent transition from sol to gel with large volume change may be seen in the former type of thermosensitive hydrogels and is negligible in CMC/ CMT dependent systems. The change in volume leads to exclusion of water molecules, resulting in shrinking and stiffening of system above the transition temperature. The volume change can be undesired when cells are to be incorporated in the system. The gelation in the latter case is mainly driven by micelle formation above the transition temperature and further colloidal packing of micelles around the gelation temperature. As the gelation mainly depends on concentration of polymer, such a system could undergo fast dissolution upon addition of solvent. Here, it was envisioned to realize a thermosensitive gel based on two components, one responsible for a change in mechanical properties by formation of reversible netpoints upon heating without volume change, and second component conferring degradability on demand. As first component, an ABA triblockcopolymer (here: Poly(ethylene glycol)-b-poly(propylene glycol)-b-poly(ethylene glycol) (PEPE) with thermosensitive properties, whose sol-gel transition on the molecular level is based on micellization and colloidal jamming of the formed micelles was chosen, while for the additional macromolecular component crosslinking the formed micelles biopolymers were employed. The synthesis of the hydrogels was performed in two ways, either by physical mixing of compounds showing electrostatic interactions, or by covalent coupling of the components. Biopolymers (here: the polysaccharides hyaluronic acid, chondroitin sulphate, or pectin, as well as the protein gelatin) were employed as additional macromolecular crosslinker to simultaneously incorporate an enzyme responsiveness into the systems. In order to have strong ionic/electrostatic interactions between PEPE and polysaccharides, PEPE was aminated to yield predominantly mono- or di-substituted PEPEs. The systems based on aminated PEPE physically mixed with HA showed an enhancement in the mechanical properties such as, elastic modulus (G′) and viscous modulus (G′′) and a decrease of the gelation temperature (Tgel) compared to the PEPE at same concentration. Furthermore, by varying the amount of aminated PEPE in the composition, the Tgel of the system could be tailored to 27-36 °C. The physical mixtures of HA with di-amino PEPE (HA·di-PEPE) showed higher elastic moduli G′ and stability towards dissolution compared to the physical mixtures of HA with mono-amino PEPE (HA·mono-PEPE). This indicates a strong influence of electrostatic interaction between -COOH groups of HA and -NH2 groups of PEPE. The physical properties of HA with di-amino PEPE (HA·di-PEPE) compare beneficially with the physical properties of the human vitreous body, the systems are highly transparent, and have a comparable refractive index and viscosity. Therefore,this material was tested for a potential biological application and was shown to be non-cytotoxic in eluate and direct contact tests. The materials will in the future be investigated in further studies as vitreous body substitutes. In addition, enzymatic degradation of these hydrogels was performed using hyaluronidase to specifically degrade the HA. During the degradation of these hydrogels, increase in the Tgel was observed along with decrease in the mechanical properties. The aminated PEPE were further utilised in the covalent coupling to Pectin and chondroitin sulphate by using EDC as a coupling agent. Here, it was possible to adjust the Tgel (28-33 °C) by varying the grafting density of PEPE to the biopolymer. The grafting of PEPE to Pectin enhanced the thermal stability of the hydrogel. The Pec-g-PEPE hydrogels were degradable by enzymes with slight increase in Tgel and decrease in G′ during the degradation time. The covalent coupling of aminated PEPE to HA was performed by DMTMM as a coupling agent. This method of coupling was observed to be more efficient compared to EDC mediated coupling. Moreover, the purification of the final product was performed by ultrafiltration technique, which efficiently removed the unreacted PEPE from the final product, which was not sufficiently achieved by dialysis. Interestingly, the final products of these reaction were in a gel state and showed enhancement in the mechanical properties at very low concentrations (2.5 wt\%) near body temperature. In these hydrogels the resulting increase in mechanical properties was due to the combined effect of micelle packing (physical interactions) by PEPE and covalent netpoints between PEPE and HA. PEPE alone or the physical mixtures of the same components were not able to show thermosensitive behavior at concentrations below 16 wt\%. These thermosensitive hydrogels also showed on demand solubilisation by enzymatic degradation. The concept of thermosensitivity was introduced to 3D architectured porous hydrogels, by covalently grafting the PEPE to gelatin and crosslinking with LDI as a crosslinker. Here, the grafted PEPE resulted in a decrease in the helix formation in gelatin chains and after fixing the gelatin chains by crosslinking, the system showed an enhancement in the mechanical properties upon heating (34-42 °C) which was reversible upon cooling. A possible explanation of the reversible changes in mechanical properties is the strong physical interactions between micelles formed by PEPE being covalently linked to gelatin. Above the transition temperature, the local properties were evaluated by AFM indentation of pore walls in which an increase in elastic modulus (E) at higher temperature (37 °C) was observed. The water uptake of these thermosensitive architectured porous hydrogels was also influenced by PEPE and temperature (25 °C and 37 °C), showing lower water up take at higher temperature and vice versa. In addition, due to the lower water uptake at high temperature, the rate of hydrolytic degradation of these systems was found to be decreased when compared to pure gelatin architectured porous hydrogels. Such temperature sensitive architectured porous hydrogels could be important for e.g. stem cell culturing, cell differentiation and guided cell migration, etc. Altogether, it was possible to demonstrate that the crosslinking of micelles by a macromolecular crosslinker increased the shear moduli, viscosity, and stability towards dissolution of CMC-based gels. This effect could be likewise be realized by covalent or non-covalent mechanisms such as, micelle interactions, physical interactions of gelatin chains and physical interactions between gelatin chains and micelles. Moreover, the covalent grafting of PEPE will create additional net-points which also influence the mechanical properties of thermosensitive architectured porous hydrogels. Overall, the physical and chemical interactions and reversible physical interactions in such thermosensitive architectured porous hydrogels gave a control over the mechanical properties of such complex system. The hydrogels showing change of mechanical properties without a sol-gel transition or volume change are especially interesting for further study with cell proliferation and differentiation.},
  language  = {en}
}
@phdthesis{Mondal2013,
  author    = {Mondal, Suvendu Sekhar},
  title     = {Design of isostructural metal-imidazolate frameworks : application for gas storage},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-69692},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {The sharply rising level of atmospheric carbon dioxide resulting from anthropogenic emissions is one of the greatest environmental concerns facing our civilization today. Metal-organic frameworks (MOFs) are a new class of materials that constructed by metal-containing nodes bonded to organic bridging ligands. MOFs could serve as an ideal platform for the development of next generation CO2 capture materials owing to their large capacity for the adsorption of gases and their structural and chemical tunability. The ability to rationally select the framework components is expected to allow the affinity of the internal pore surface toward CO2 to be precisely controlled, facilitating materials properties that are optimized for the specific type of CO2 capture to be performed (post-combustion capture, precombustion capture, or oxy-fuel combustion) and potentially even for the specific power plant in which the capture system is to be installed. For this reason, significant effort has been made in recent years in improving the gas separation performance of MOFs and some studies evaluating the prospects of deploying these materials in real-world CO2 capture systems have begun to emerge. We have developed six new MOFs, denoted as IFPs (IFP-5, -6, -7, -8, -9, -10, IFP = Imidazolate Framework Potsdam) and two hydrogen-bonded molecular building block (MBB, named as 1 and 2 for Zn and Co based, respectively) have been synthesized, characterized and applied for gas storage. The structure of IFP possesses 1D hexagonal channels. Metal centre and the substituent groups of C2 position of the linker protrude into the open channels and determine their accessible diameter. Interestingly, the channel diameters (range : 0.3 to 5.2 {\AA}) for IFP structures are tuned by the metal centre (Zn, Co and Cd) and substituent of C2 position of the imidazolate linker. Moreover hydrogen bonded MBB of 1 and 2 is formed an in situ functionalization of a ligand under solvothermal condition. Two different types of channels are observed for 1 and 2. Materials contain solvent accessible void space. Solvent could be easily removed by under high vacuum. The porous framework has maintained the crystalline integrity even without solvent molecules. N2, H2, CO2 and CH4 gas sorption isotherms were performed. Gas uptake capacities are comparable with other frameworks. Gas uptake capacity is reduced when the channel diameter is narrow. For example, the channel diameter of IFP-5 (channel diameter: 3.8 {\AA}) is slightly lower than that of IFP-1 (channel diameter: 4.2 {\AA}); hence, the gas uptake capacity and Brunauer-Emmett-Teller (BET) surface area are slightly lower than IFP-1. The selectivity does not depend only on the size of the gas components (kinetic diameter: CO2 3.3 {\AA}, N2 3.6 {\AA} and CH4 3.8 ) but also on the polarizability of the surface and of the gas components. IFP-5 and-6 have the potential applications for the separation of CO2 and CH4 from N2-containing gas mixtures and CO2 and CH4 containing gas mixtures. Gas sorption isotherms of IFP-7, -8, -9, -10 exhibited hysteretic behavior due to flexible alkoxy (e.g., methoxy and ethoxy) substituents. Such phenomenon is a kind of gate effects which is rarely observed in microporous MOFs. IFP-7 (Zn-centred) has a flexible methoxy substituent. This is the first example where a flexible methoxy substituent shows the gate opening behavior in a MOF. Presence of methoxy functional group at the hexagonal channels, IFP-7 acted as molecular gate for N2 gas. Due to polar methoxy group and channel walls, wide hysteretic isotherm was observed during gas uptake. The N2 The estimated BET surface area for 1 is 471 m2 g-1 and the Langmuir surface area is 570 m2 g-1. However, such surface area is slightly higher than azolate-based hydrogen-bonded supramolecular assemblies and also comparable and higher than some hydrogen-bonded porous organic molecules.},
  language  = {en}
}
@phdthesis{Titirici2013,
  author    = {Titirici, Maria-Magdalena},
  title     = {Hydrothermal carbonisation},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-66885},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {The world's appetite for energy is producing growing quantities of CO2, a pollutant that contributes to the warming of the planet and which currently cannot be removed or stored in any significant way. Other natural reserves are also being devoured at alarming rates and current assessments suggest that we will need to identify alternative sources in the near future. With the aid of materials chemistry it should be possible to create a world in which energy use needs not be limited and where usable energy can be produced and stored wherever it is needed, where we can minimize and remediate emissions as new consumer products are created, whilst healing the planet and preventing further disruptive and harmful depletion of valuable mineral assets. In achieving these aims, the creation of new and very importantly greener industries and new sustainable pathways are crucial. In all of the aforementioned applications, new materials based on carbon, ideally produced via inexpensive, low energy consumption methods, using renewable resources as precursors, with flexible morphologies, pore structures and functionalities, are increasingly viewed as ideal candidates to fulfill these goals. The resulting materials should be a feasible solution for the efficient storage of energy and gases. At the end of life, such materials ideally must act to improve soil quality and to act as potential CO2 storage sinks. This is exactly the subject of this habilitation thesis: an alternative technology to produce carbon materials from biomass in water using low carbonisation temperatures and self-generated pressures. This technology is called hydrothermal carbonisation. It has been developed during the past five years by a group of young and talented researchers working under the supervision of Dr. Titirici at the Max-Planck Institute of Colloids and Interfaces and it is now a well-recognised methodology to produce carbon materials with important application in our daily lives. These applications include electrodes for portable electronic devices, filters for water purification, catalysts for the production of important chemicals as well as drug delivery systems and sensors.},
  language  = {en}
}
@phdthesis{Robinson2013,
  author    = {Robinson, Joshua Wayne},
  title     = {Novel Poly(N-substituted glycine)s : synthesis, post-modification, and physical properties},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-64789},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {Various synthetic approaches were explored towards the preparation of poly(N-substituted glycine) homo/co-polymers (a.k.a. polypeptoids). In particular, monomers that would facilitate in the preparation of bio-relevant polymers via either chain- or step-growth polymerization were targeted. A 3-step synthetic approach towards N-substituted glycine N-carboxyanhydrides (NNCA) was implemented, or developed, and optimized allowing for an efficient gram scale preparation of the aforementioned monomer (chain-growth). After exploring several solvents and various conditions, a reproducible and efficient ring-opening polymerization (ROP) of NNCAs was developed in benzonitrile (PhCN). However, achieving molecular weights greater than 7 kDa required longer reaction times (>4 weeks) and sub-sequentially allowed for undesirable competing side reactions to occur (eg. zwitterion monomer mechanisms). A bulk-polymerization strategy provided molecular weights up to 11 kDa within 24 hours but suffered from low monomer conversions (ca. 25\%). Likewise, a preliminary study towards alcohol promoted ROP of NNCAs suffered from impurities and a suspected alternative activated monomer mechanism (AAMM) providing poor inclusion of the initiator and leading to multi-modal dispersed polymeric systems. The post-modification of poly(N-allyl glycine) via thiol-ene photo-addition was observed to be quantitative, with the utilization of photo-initiators, and facilitated in the first glyco-peptoid prepared under environmentally benign conditions. Furthermore, poly(N-allyl glycine) demonstrated thermo-responsive behavior and could be prepared as a semi-crystalline bio-relevant polymer from solution (ie. annealing). Initial efforts in preparing these polymers via standard poly-condensation protocols were insufficient (step-growth). However, a thermally induced side-product, diallyl diketopiperazine (DKP), afforded the opportunity to explore photo-induced thiol-ene and acyclic diene metathesis (ADMET) polymerizations. Thiol-ene polymerization readily led to low molecular weight polymers (<2.5 kDa), that were insoluble in most solvents except heated amide solvents (ie. DMF), whereas ADMET polymerization, with diallyl DKP, was unsuccessful due to a suspected 6 member complexation/deactivation state of the catalyst. This understanding prompted the preparation of elongated DKPs most notably dibutenyl DKP. SEC data supports the aforementioned understanding but requires further optimization studies in both the preparation of the DKP monomers and following ADMET polymerization. This work was supported by NMR, GC-MS, FT-IR, SEC-IR, and MALDI-Tof MS characterization. Polymer properties were measured by UV-Vis, TGA, and DSC.},
  language  = {en}
}
@phdthesis{Glatzel2013,
  author    = {Glatzel, Stefan},
  title     = {Cellulose based transition metal nano-composites : structuring and development},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-64678},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {Cellulose is the most abundant biopolymer on earth. In this work it has been used, in various forms ranging from wood to fully processed laboratory grade microcrystalline cellulose, to synthesise a variety of metal and metal carbide nanoparticles and to establish structuring and patterning methodologies that produce highly functional nano-hybrids. To achieve this, the mechanisms governing the catalytic processes that bring about graphitised carbons in the presence of iron have been investigated. It was found that, when infusing cellulose with an aqueous iron salt solution and heating this mixture under inert atmosphere to 640 °C and above, a liquid eutectic mixture of iron and carbon with an atom ratio of approximately 1:1 forms. The eutectic droplets were monitored with in-situ TEM at the reaction temperature where they could be seen dissolving amorphous carbon and leaving behind a trail of graphitised carbon sheets and subsequently iron carbide nanoparticles. These transformations turned ordinary cellulose into a conductive and porous matrix that is well suited for catalytic applications. Despite these significant changes on the nanometre scale the shape of the matrix as a whole was retained with remarkable precision. This was exemplified by folding a sheet of cellulose paper into origami cranes and converting them via the temperature treatment in to magnetic facsimiles of those cranes. The study showed that the catalytic mechanisms derived from controlled systems and described in the literature can be transferred to synthetic concepts beyond the lab without loss of generality. Once the processes determining the transformation of cellulose into functional materials were understood, the concept could be extended to other metals and metal-combinations. Firstly, the procedure was utilised to produce different ternary iron carbides in the form of MxFeyC (M = W, Mn). None of those ternary carbides have thus far been produced in a nanoparticle form. The next part of this work encompassed combinations of iron with cobalt, nickel, palladium and copper. All of those metals were also probed alone in combination with cellulose. This produced elemental metal and metal alloy particles of low polydispersity and high stability. Both features are something that is typically not associated with high temperature syntheses and enables to connect the good size control with a scalable process. Each of the probed reactions resulted in phase pure, single crystalline, stable materials. After showing that cellulose is a good stabilising and separating agent for all the investigated types of nanoparticles, the focus of the work at hand is shifted towards probing the limits of the structuring and pattering capabilities of cellulose. Moreover possible post-processing techniques to further broaden the applicability of the materials are evaluated. This showed that, by choosing an appropriate paper, products ranging from stiff, self-sustaining monoliths to ultra-thin and very flexible cloths can be obtained after high temperature treatment. Furthermore cellulose has been demonstrated to be a very good substrate for many structuring and patterning techniques from origami folding to ink-jet printing. The thereby resulting products have been employed as electrodes, which was exemplified by electrodepositing copper onto them. Via ink-jet printing they have additionally been patterned and the resulting electrodes have also been post functionalised by electro-deposition of copper onto the graphitised (printed) parts of the samples. Lastly in a preliminary test the possibility of printing several metals simultaneously and thereby producing finely tuneable gradients from one metal to another have successfully been made. Starting from these concepts future experiments were outlined. The last chapter of this thesis concerned itself with alternative synthesis methods of the iron-carbon composite, thereby testing the robustness of the devolved reactions. By performing the synthesis with partly dissolved scrap metal and pieces of raw, dry wood, some progress for further use of the general synthesis technique were made. For example by using wood instead of processed cellulose all the established shaping techniques available for wooden objects, such as CNC milling or 3D prototyping, become accessible for the synthesis path. Also by using wood its intrinsic well defined porosity and the fact that large monoliths are obtained help expanding the prospect of using the composite. It was also demonstrated in this chapter that the resulting material can be applied for the environmentally important issue of waste water cleansing. Additionally to being made from renewable resources and by a cheap and easy one-pot synthesis, the material is recyclable, since the pollutants can be recovered by washing with ethanol. Most importantly this chapter covered experiments where the reaction was performed in a crude, home-built glass vessel, fuelled - with the help of a Fresnel lens - only by direct concentrated sunlight irradiation. This concept carries the thus far presented synthetic procedures from being common laboratory syntheses to a real world application. Based on cellulose, transition metals and simple equipment, this work enabled the easy one-pot synthesis of nano-ceramic and metal nanoparticle composites otherwise not readily accessible. Furthermore were structuring and patterning techniques and synthesis routes involving only renewable resources and environmentally benign procedures established here. Thereby it has laid the foundation for a multitude of applications and pointed towards several future projects reaching from fundamental research, to application focussed research and even and industry relevant engineering project was envisioned.},
  language  = {en}
}