@article{WinterZabelStrauch2012,
  author    = {Winter, Alette and Zabel, Andre and Strauch, Peter},
  title     = {Tetrachloridocuprates(II)-Synthesis and Electron Paramagnetic Resonance (EPR) Spectroscopy},
  series = {International journal of molecular sciences},
  volume    = {13},
  journal   = {International journal of molecular sciences},
  number    = {2},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1661-6596},
  doi       = {10.3390/ijms13021612},
  pages     = {1612 -- 1619},
  year      = {2012},
  abstract  = {Ionic liquids (ILs) on the basis of metal containing anions and/or cations are of interest for a variety of technical applications e.g., synthesis of particles, magnetic or thermochromic materials. We present the synthesis and the results of electron paramagnetic resonance (EPR) spectroscopic analyses of a series of some new potential ionic liquids based on tetrachloridocuprates(II), [CuCl4](2-), with different sterically demanding cations: hexadecyltrimethylammonium 1, tetradecyltrimethylammonium 2, tetrabutylammonium 3 and benzyltriethylammonium 4. The cations in the new compounds were used to achieve a reasonable separation of the paramagnetic Cu(II) ions for EPR spectroscopy. The EPR hyperfine structure was not resolved. This is due to the exchange broadening, resulting from still incomplete separation of the paramagnetic Cu(II) centers. Nevertheless, the principal values of the electron Zeemann tensor (g parallel to and g perpendicular to) of the complexes could be determined. Even though the solid substances show slightly different colors, the UV/Vis spectra are nearly identical, indicating structural changes of the tetrachloridocuprate moieties between solid state and solution. The complexes have a promising potential e.g., as high temperature ionic liquids, as precursors for the formation of copper chloride particles or as catalytic paramagnetic ionic liquids.},
  language  = {en}
}
@article{AwadSchildeStrauch2011,
  author    = {Awad, Duha Jawad and Schilde, Uwe and Strauch, Peter},
  title     = {4,4 '-Bis(tert-butyl)-2,2 '-bipyridinedichlorometal(II) - Synthesis, structure and EPR spectroscopy},
  series = {Inorganica chimica acta : the international inorganic chemistry journal},
  volume    = {365},
  journal   = {Inorganica chimica acta : the international inorganic chemistry journal},
  number    = {1},
  publisher = {Elsevier},
  address   = {Lausanne},
  issn      = {0020-1693},
  doi       = {10.1016/j.ica.2010.08.035},
  pages     = {127 -- 132},
  year      = {2011},
  abstract  = {Due to the better solubility of the 4,4'-substituted bipyridine ligand a series of 4,4'0-bis(tert-butyl)-2,2'-bipyridinedichlorometal(II) complexes, [M(tbbpy)Cl(2)], with M = Cu, Ni, Zn, Pd, Pt was synthesised and characterised. The blue copper complex 4,4'-bis(tert-butyl)-2,2'-bipyridinedichlorocopper(II) was isolated in two different polymorphic forms, as prisms 1 with a solvent inclusion and solvent-free as needles 2. Both structures were determined by X-ray structure analysis. They crystallise in the monoclinic space group P2(1)/c with four molecules in the unit cell, but with different unit cells and packing motifs. Whereas in the prisms 1, with the unit cell parameters a = 12.1613(12), b = 10.6363(7), c = 16.3074(15) angstrom, eta = 94.446(8)degrees, the packing is dominated by intra-and intermolecular hydrogen bonds, in the needles 2, with a = 7.738(1), b = 18. 333(2), c = 13.291(3) angstrom, beta = 97.512(15)degrees, only intramolecular hydrogen bonds appear and the complex molecules are arranged in columns which are stabilised by p-p-stacking interactions. In both complexes the copper has a tetrahedrally distorted coordination sphere. These copper complexes were also studied by EPR spectroscopy in solution, as frozen glass and diamagnetically diluted powder with the analogue [Pd(tbbpy)Cl(2)] as host lattice.},
  language  = {en}
}
@article{StrauchKossmannKellingetal.2016,
  author    = {Strauch, Peter and Kossmann, Alexander and Kelling, Alexandra and Schilde, Uwe},
  title     = {EPR on bis(1,2-dithiosquarato)cuprate(II) in the bis(1,2-dithiosquarato)nickelate(II) host lattice - structure and spectroscopy},
  series = {Chemical papers},
  volume    = {70},
  journal   = {Chemical papers},
  publisher = {De Gruyter},
  address   = {Berlin},
  issn      = {0366-6352},
  doi       = {10.1515/chempap-2015-0154},
  pages     = {61 -- 68},
  year      = {2016},
  abstract  = {EPR spectroscopy is a well suited analytical tool to monitor the electronic situation around paramagnetic metal centres as copper(II) and therefore the structural influences on the paramagnetic ion. 1,2-Dithiosquaratometalates are available by direct synthesis from metal salts with dipotassium-1,2-dithiosquarate and the appropriate counter cations. Synthesis and characterisation of bis(benzyltributylammonium)1,2-dithiosquaratonickelate(II), (BzlBu(3)N)(2)[Ni(dtsq)(2)], and bis(benzyltributylammonium)1,2-dithiosquaratocuprate(II), (BzlBu(3)N)(2)[Cu(dtsq)(2)], with benzyltributylammonium as the counter ion is reported and the X-ray structures of two complexes, (BzlBu(3)N)(2)[Ni(dtsq)(2)] and (BzlBu(3)N)(2)[Cu(dtsq)(2)], are presented. Both complexes, crystallising in the monoclinic space group P2(1)/c, are isostructural with only small differences in the coordination sphere due to the different metal ions. The diamagnetic nickel complex is therefore well suited as a host lattice for the paramagnetic Cu(II) complex to measure EPR for additional structural information. (c) 2015 Institute of Chemistry, Slovak Academy of Sciences},
  language  = {en}
}
@article{ZabelWinterKellingetal.2016,
  author    = {Zabel, Andre and Winter, Alette and Kelling, Alexandra and Schilde, Uwe and Strauch, Peter},
  title     = {Tetrabromidocuprates(II)-Synthesis, Structure and EPR},
  series = {International journal of molecular sciences},
  volume    = {17},
  journal   = {International journal of molecular sciences},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1422-0067},
  doi       = {10.3390/ijms17040596},
  pages     = {14},
  year      = {2016},
  abstract  = {Metal-containing ionic liquids (ILs) are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II) with several "onium" cations in comparison to the results of electron paramagnetic resonance (EPR) spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II) ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II) centres. For the majority of compounds, the principal g values (g|| and g(perpendicular to)) of the tensors could be determined and information on the structural changes in the [CuBr4](2-) anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids.},
  language  = {en}
}
@misc{KoenigKellingSchildeetal.2017,
  author    = {K{\"o}nig, Jana and Kelling, Alexandra and Schilde, Uwe and Strauch, Peter},
  title     = {[µ2-O,O′,Oʺ,Oʺ′-Bis(1,2-dithiooxalato-S,S′)nickel(II)]bis[-O,O′-bis(1,2-dithiooxalato-S,S′)-nickel(II)pentaquaholmium(III)]hydrate, [Ho2Ni3(dto)6(H2O)10]},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-400598},
  pages     = {5},
  year      = {2017},
  abstract  = {Planar bis(1,2-dithiooxalato)nickelate(II), [Ni(dto)]2- reacts in aqueous solutions with lanthanide ions (Ln3+) to form pentanuclear, hetero-bimetallic complexes of the general composition [{Ln(H2O)n}2{Ni(dto)2}3]·xH2O. (n = 4 or 5; x = 9-12). The complex [{Ho(H2O)5}2{Ni(dto)2}3]·10H2O, Ho2Ni3, was synthesized and characterized by single crystal X-ray structure analysis and powder diffraction. The Ho2Ni3 complex crystallizes as monoclinic crystals in the space group P21/c. The channels and cavities, appearing in the crystal packing of the complex molecules, are occupied by a varying amount of non-coordinated water molecules.},
  language  = {en}
}
@article{StrauchNeumannKellingetal.2015,
  author    = {Strauch, Peter and Neumann, Mike and Kelling, Alexandra and Schilde, Uwe},
  title     = {Bis(1,2-dithiosquarato)nickelates(II): Synthesis, Structure, EPR and Thermal Behavior},
  series = {Acta chimica Slovenica},
  volume    = {62},
  journal   = {Acta chimica Slovenica},
  number    = {2},
  publisher = {Drustvo},
  address   = {Ljubljana},
  issn      = {1318-0207},
  pages     = {288 -- 296},
  year      = {2015},
  abstract  = {1,2-Dithiosquaratonickelates are available by direct synthesis from metal salts with dipotassium-1,2-dithiosquarate and the appropriate counter cations. The synthesis and characterization, including mass spectrometry, of a series 1,2-dithiosquaratonickelates(II), [Ni(dtsq)(2)](2-), with several "onium" cations is reported and the X-ray structures of two diamagnetic complexes, (HexPh(3)P)(2)[Ni(dtsq)(2)] and (BuPh3P)(2)[Ni(dtsq)(2)] with sterically demanding counter ions are presented. The diamagnetic nickel complexes have been doped as host lattices with traces of Cu(II) to measure EPR for additional structural information. The thermal behavior of this series is studied by thermogravimetry and differential thermal analysis (TG/DTA). The thermolysis in air as well as under nitrogen atmosphere of these complexes results in nickel oxide nano-particles in all cases, which are characterized by X-ray powder diffraction.},
  language  = {en}
}
@article{GuelzowHoernerStrauchetal.2017,
  author    = {Guelzow, Jana and Hoerner, Gerald and Strauch, Peter and Stritt, Anika and Irran, Elisabeth and Grohmann, Andreas},
  title     = {Oxygen Delivery as a Limiting Factor in Modelling Dicopper(II) Oxidase Reactivity},
  series = {Chemistry - a European journal},
  volume    = {23},
  journal   = {Chemistry - a European journal},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0947-6539},
  doi       = {10.1002/chem.201605868},
  pages     = {7009 -- 7023},
  year      = {2017},
  abstract  = {Deprotonation of ligand-appended alkoxyl groups in mononuclear copper(II) complexes of N,O ligands L-1 and L-2, gave dinuclear complexes sharing symmetrical Cu2O2 cores. Molecular structures of these mono-and binuclear complexes have been characterized by XRD, and their electronic structures by UV/Vis, H-1 NMR, EPR and DFT; moreover, catalytic performance as models of catechol oxidase was studied. The binuclear complexes with anti-ferromagnetically coupled copper(II) centers are moderately active in quinone formation from 3,5-di-tert-butyl-catechol under the estab-lished conditions of oxygen saturation, but are strongly activated when additional dioxygen is administered during catalytic turnover. This unforeseen and unprecedented effect is attributed to increased maximum reaction rates v(max), whereas the substrate affinity KM remains unaffected. Oxygen administration is capable of (partially) removing limitations to turnover caused by product inhibition. Because product inhibition is generally accepted to be a major limitation of catechol oxidase models, we think that our observations will be applicable more widely.},
  language  = {en}
}
@article{KozlevcarGolobicStrauch2006,
  author    = {Kozlevcar, Bojan and Golobic, Amalija and Strauch, Peter},
  title     = {Dynamic pseudo Jahn-Teller distortion in a compressed octahedral CuO6 complex},
  series = {Polyhedron : the international journal of inorganic and organometallic chemistry},
  volume    = {25},
  journal   = {Polyhedron : the international journal of inorganic and organometallic chemistry},
  number    = {15},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0277-5387},
  doi       = {10.1016/j.poly.2006.04.009},
  pages     = {2824 -- 2828},
  year      = {2006},
  abstract  = {The crystal structure of cis-[Cu(C8H7O3)(2)(H2O)(2)] (115 K data) reveals bidentate vanillinate ions coordinated via methoxy and deprotonated hydroxy oxygen atoms and water molecules in a distorted octahedral CuO6 chromophore. A cis orientation of the ligands enables two non-identical O(methoxy)-Cu-O(water) coordination axes (2.354(l) + 2.163(1); 2.151(1) + 2.020(1) angstrom), and the third shortest O(hydroxy)-Cu-O(hydroxy) axis (1.919(1) + 1.914(1) angstrom). This 115 K coordination sphere differs importantly to the one obtained from the 293 K data of the same compound, where two long 0(methoxy)-Cu-O(water) axes are of the same length, and only minor changes at the short 0(hydroxy)-Cu-O(hydroxy) axis are noticed. An axial symmetry of the complex with an inverse g(1.2)(g(perpendicular to)) > g(3)(g(parallel to)) pattern is observed in the temperature range from 298 to 180 K. A further decrease of temperature reveals gradual changes from axial to rhombic symmetry (g(1) > g(2) > g(3)) that is reversible. A mean-square displacement amplitude (MDSA) analysis reveals a disorder in the Cu-O(methoxy) bonds, but not in the other metal-ligand Cu-O(hydroxy) and Cu-O(water) bonds at 293 and 115 K. The disorder is significantly weaker in the 115 K structure. The MSDA analysis and the structural-EPR agreement show vibrational disorder in two coordination axes, due to the cis conformation of the complex with two 0(methoxy)-Cu-O(water) axes.},
  language  = {en}
}
@article{AyiKhareStrauchetal.2010,
  author    = {Ayi, Ayi A. and Khare, Varsha and Strauch, Peter and Girard, J{\`e}r{\^o}me and Fromm, Katharina M. and Taubert, Andreas},
  title     = {On the chemical synthesis of titanium nanoparticles from ionic liquids},
  issn      = {0026-9247},
  doi       = {10.1007/s00706-010-0403-4},
  year      = {2010},
  abstract  = {We report on attempts towards the synthesis of titanium nanoparticles using a wet chemical approach in imidazolium-based ionic liquids (ILs) under reducing conditions. Transmission electron microscopy finds nanoparticles in all cases. UV/Vis spectroscopy confirms the nanoparticulate nature of the precipitate, as in all cases an absorption band between ca. 280 and 300 nm is visible. IR spectroscopy shows that even after extensive washing and drying, some IL remains adsorbed on the nanoparticles. Raman spectroscopy suggests the formation of anatase nanoparticles, but X-ray diffraction reveals that, possibly, amorphous titania forms or that the nanoparticles are so small that a clear structure assignment is not possible. The report thus shows that (possibly amorphous) titanium oxides even form under reducing conditions and that the chemical synthesis of titanium nanoparticles in ILs remains elusive.},
  language  = {en}
}
@article{NeumannNoeskeTaubertetal.2012,
  author    = {Neumann, Mike and Noeske, Robert and Taubert, Andreas and Tiersch, Brigitte and Strauch, Peter},
  title     = {Highly structured, biomorphous beta-SiC with high specific surface area from Equisetaceae},
  series = {Journal of materials chemistry},
  volume    = {22},
  journal   = {Journal of materials chemistry},
  number    = {18},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {0959-9428},
  doi       = {10.1039/c2jm30253e},
  pages     = {9046 -- 9051},
  year      = {2012},
  abstract  = {Mesoporous, highly structured silicon carbide (beta-SiC) was synthesised from renewable plant materials (two Equisetaceae species) in a one-step carbothermal process at remarkably low temperatures down to 1200 degrees C. The SiC precursor is a silicon-carbon mixture with finely dispersed carbon prepared by pyrolysis of the organic plant matrix. Yields are 3 to 100\% (omega(Si/Si) related to the silicon deposited in the plant material), depending on reaction temperature and time. IR spectroscopy, X-ray diffraction, and nitrogen sorption prove the formation of high-purity beta-SiC with minor inorganic impurities after purification and a high specific surface area of up to 660 m(2) g(-1). Scanning electron microscopy shows that the plant morphology is maintained in the final SiC. Sedimentation analysis finds a mean particle size (diameters d(50)) of 20 mu m.},
  language  = {en}
}