TY  - JOUR
A1  - Mondal, Suvendu Sekhar
A1  - Behrens, Karsten
A1  - Kelling, Alexandra
A1  - Nabein, Hans-Peter
A1  - Schilde, Uwe
A1  - Holdt, Hans-Jürgen
T1  - Two Cd-II/Co-II-Imidazolate Coordination Polymers: Syntheses, Crystal Structures, Stabilities, and Luminescent/Magnetic Properties
JF  - Zeitschrift für anorganische und allgemeine Chemie
N2  - Cadmium(II) based 2D coordination polymer [Cd(L1)(2)(DMF)(2)] (1) (L1 = 4,5-dicyano-2-methylimidazolate, DMF = N,N'-dimethylformamide) and 2D cobalt(II)-imidazolate framework [Co(L3)(4)] (2) (L3 = 4,5-diamide-2-ethoxyimidazolate) were synthesized under solvothermal reaction conditions. The materials were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction measurement (PXRD) and single-crystal X-ray diffraction. Compound 1 has hexacoordinate Cd-II ions and forms a zigzag chain-like coordination polymer structure, whereas compound 2 exhibits a 2D square grid type structure. The thermal stability analysis reveals that 2 showed an exceptional thermal stability up to 360 degrees C. Also, 2 maintained its fully crystalline integrity in boiling water as confirmed by PXRD. The solid state luminescent property of 1 was not observed at room temperature. Compound 2 showed an independent high spin central Co-II atom.
KW  - Cobalt
KW  - Cadmium
KW  - Coordination polymers
KW  - Crystal structures
KW  - Imidazole
Y1  - 2015
U6  - https://doi.org/10.1002/zaac.201500526
SN  - 0044-2313
SN  - 1521-3749
VL  - 641
IS  - 11
SP  - 1991
EP  - 1997
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Behrens, Karsten
A1  - Balischewski, Christian
A1  - Sperlich, Eric
A1  - Menski, Antonia Isabell
A1  - Balderas-Valadez, Ruth Fabiola
A1  - Pacholski, Claudia
A1  - Günter, Christina
A1  - Lubahn, Susanne
A1  - Kelling, Alexandra
A1  - Taubert, Andreas
T1  - Mixed chloridometallate(ii) ionic liquids with tunable color and optical response for potential ammonia sensors
T2  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Eight d-metal-containing N-butylpyridinium ionic liquids (ILs) with the nominal composition (C4Py)2[Ni0.5M0.5Cl4] or (C4Py)2[Zn0.5M0.5Cl4] (M = Cu, Co, Mn, Ni, Zn; C4Py = N-butylpyridinium) were synthesized, characterized, and investigated for their optical properties. Single crystal and powder X-ray analysis shows that the compounds are isostructural to existing examples based on other d-metal ions. Inductively coupled plasma optical emission spectroscopy measurements confirm that the metal/metal ratio is around 50 : 50. UV-Vis spectroscopy shows that the optical absorption can be tuned by selection of the constituent metals. Moreover, the compounds can act as an optical sensor for the detection of gases such as ammonia as demonstrated via a simple prototype setup.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1316 
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-587512
SN  - 1866-8372
IS  - 1316
SP  - 35072
EP  - 35082
ER  - 
TY  - JOUR
A1  - Balischewski, Christian
A1  - Behrens, Karsten
A1  - Zehbe, Kerstin
A1  - Günter, Christina
A1  - Mies, Stefan
A1  - Sperlich, Eric
A1  - Kelling, Alexandra
A1  - Taubert, Andreas
T1  - Ionic liquids with more than one metal
BT  - optical and rlectrochemical properties versus d-block metal vombinations
JF  - Chemistry - a European journal
N2  - Thirteen N-butylpyridinium salts, including three monometallic [C4Py](2)[MCl4], nine bimetallic [C4Py](2)[(M1-xMxCl4)-M-a-Cl-b] and one trimetallic compound [C4Py](2)[(M1-y-zMyMz (c) Cl4)-M-a-M-b] (M=Co, Cu, Mn; x=0.25, 0.50 or 0.75 and y=z=0.33), were synthesized and their structure and thermal and electrochemical properties were studied. All compounds are ionic liquids (ILs) with melting points between 69 and 93 degrees C. X-ray diffraction proves that all ILs are isostructural. The conductivity at room temperature is between 10(-4) and 10(-8) S cm(-1). Some Cu-based ILs reach conductivities of 10(-2) S cm(-1), which is, however, probably due to IL dec. This correlates with the optical bandgap measurements indicating the formation of large bandgap semiconductors. At elevated temperatures approaching the melting points, the conductivities reach up to 1.47x10(-1) S cm(-1) at 70 degrees C. The electrochemical stability windows of the ILs are between 2.5 and 3.0 V.
KW  - bandgap
KW  - electrochemistry
KW  - ionic liquids
KW  - metal-containing ionic
KW  - liquids
KW  - tetrahalido metallates
Y1  - 2020
U6  - https://doi.org/10.1002/chem.202003097
SN  - 0947-6539
SN  - 1521-3765
VL  - 26
IS  - 72
SP  - 17504
EP  - 17513
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Behrens, Karsten
A1  - Balischewski, Christian
A1  - Sperlich, Eric
A1  - Menski, Antonia Isabell
A1  - Balderas-Valadez, Ruth Fabiola
A1  - Pacholski, Claudia
A1  - Günter, Christina
A1  - Lubahn, Susanne
A1  - Kelling, Alexandra
A1  - Taubert, Andreas
T1  - Mixed chloridometallate(ii) ionic liquids with tunable color and optical response for potential ammonia sensors
JF  - RSC Advances
N2  - Eight d-metal-containing N-butylpyridinium ionic liquids (ILs) with the nominal composition (C4Py)2[Ni0.5M0.5Cl4] or (C4Py)2[Zn0.5M0.5Cl4] (M = Cu, Co, Mn, Ni, Zn; C4Py = N-butylpyridinium) were synthesized, characterized, and investigated for their optical properties. Single crystal and powder X-ray analysis shows that the compounds are isostructural to existing examples based on other d-metal ions. Inductively coupled plasma optical emission spectroscopy measurements confirm that the metal/metal ratio is around 50 : 50. UV-Vis spectroscopy shows that the optical absorption can be tuned by selection of the constituent metals. Moreover, the compounds can act as an optical sensor for the detection of gases such as ammonia as demonstrated via a simple prototype setup.
Y1  - 2022
U6  - https://doi.org/10.1039/d2ra05581c
SN  - 2046-2069
VL  - 12
SP  - 35072
EP  - 35082
PB  - RSC
CY  - London
ER  - 
TY  - JOUR
A1  - Balischewski, Christian
A1  - Bhattacharyya, Biswajit
A1  - Sperlich, Eric
A1  - Günter, Christina
A1  - Beqiraj, Alkit
A1  - Klamroth, Tillmann
A1  - Behrens, Karsten
A1  - Mies, Stefan
A1  - Kelling, Alexandra
A1  - Lubahn, Susanne
A1  - Holtzheimer, Lea
A1  - Nitschke, Anne
A1  - Taubert, Andreas
T1  - Tetrahalidometallate(II) ionic liquids with more than one metal
BT  - the effect of bromide versus chloride
JF  - Chemistry - a European journal
N2  - Fifteen N-butylpyridinium salts - five monometallic [C4Py](2)[MBr4] and ten bimetallic [C4Py](2)[(M0.5M0.5Br4)-M-a-Br-b] (M=Co, Cu, Mn, Ni, Zn) - were synthesized, and their structures and thermal and electrochemical properties were studied. All the compounds are ionic liquids (ILs) with melting points between 64 and 101 degrees C. Powder and single-crystal X-ray diffraction show that all ILs are isostructural. The electrochemical stability windows of the ILs are between 2 and 3 V. The conductivities at room temperature are between 10(-5) and 10(-6) S cm(-1). At elevated temperatures, the conductivities reach up to 10(-4) S cm(-1) at 70 degrees C. The structures and properties of the current bromide-based ILs were also compared with those of previous examples using chloride ligands, which illustrated differences and similarities between the two groups of ILs.
KW  - electrochemistry
KW  - ionic liquids
KW  - metal-containing ionic liquids;
KW  - N-butylpyridinium bromide
KW  - tetrahalidometallates
Y1  - 2022
U6  - https://doi.org/10.1002/chem.202201068
SN  - 1521-3765
VL  - 28
IS  - 64
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Debatin, Franziska
A1  - Behrens, Karsten
A1  - Weber, Jens
A1  - Baburin, Igor A.
A1  - Thomas, Arne
A1  - Schmidt, Johannes
A1  - Senkovska, Irena
A1  - Kaskel, Stefan
A1  - Kelling, Alexandra
A1  - Hedin, Niklas
A1  - Bacsik, Zoltan
A1  - Leoni, Stefano
A1  - Seifert, Gotthard
A1  - Jäger, Christian
A1  - Günter, Christina
A1  - Schilde, Uwe
A1  - Friedrich, Alwin
A1  - Holdt, Hans-Jürgen
T1  - An isoreticular family of microporous metal-organic frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate Syntheses, structures and properties
JF  - Chemistry - a European journal
N2  - We report on a new series of isoreticular frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate (IFP-14, IFP=imidazolate framework Potsdam) that form one-dimensional, microporous hexagonal channels. Varying R in the 2-substitued linker (R=Me (IFP-1), Cl (IFP-2), Br (IFP-3), Et (IFP-4)) allowed the channel diameter (4.01.7 angstrom), the polarisability and functionality of the channel walls to be tuned. Frameworks IFP-2, IFP-3 and IFP-4 are isostructural to previously reported IFP-1. The structures of IFP-2 and IFP-3 were solved by X-ray crystallographic analyses. The structure of IFP-4 was determined by a combination of PXRD and structure modelling and was confirmed by IR spectroscopy and 1H MAS and 13C CP-MAS NMR spectroscopy. All IFPs showed high thermal stability (345400?degrees C); IFP-1 and IFP-4 were stable in boiling water for 7 d. A detailed porosity analysis was performed on the basis of adsorption measurements by using various gases. The potential of the materials to undergo specific interactions with CO2 was investigated by measuring the isosteric heats of adsorption. The capacity to adsorb CH4 (at 298 K), CO2 (at 298 K) and H2 (at 77 K) at high pressure were also investigated. In situ IR spectroscopy showed that CO2 is physisorbed on IFP-14 under dry conditions and that both CO2 and H2O are physisorbed on IFP-1 under moist conditions.
KW  - adsorption
KW  - metal- organic frameworks
KW  - microporous materials
KW  - N
KW  - O ligands
KW  - zinc
Y1  - 2012
U6  - https://doi.org/10.1002/chem.201200889
SN  - 0947-6539
VL  - 18
IS  - 37
SP  - 11630
EP  - 11640
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Alrefai, Anas
A1  - Mondal, Suvendu Sekhar
A1  - Wruck, Alexander
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Brandt, Philipp
A1  - Janiak, Christoph
A1  - Schoenfeld, Sophie
A1  - Weber, Birgit
A1  - Rybakowski, Lawrence
A1  - Herrman, Carmen
A1  - Brennenstuhl, Katlen
A1  - Eidner, Sascha
A1  - Kumke, Michael Uwe
A1  - Behrens, Karsten
A1  - Günter, Christina
A1  - Müller, Holger
A1  - Holdt, Hans-Jürgen
T1  - Hydrogen-bonded supramolecular metal-imidazolate frameworks: gas sorption, magnetic and UV/Vis spectroscopic properties
JF  - Journal of Inclusion Phenomena and Macrocyclic Chemistry
N2  - By varying reaction parameters for the syntheses of the hydrogen-bonded metal-imidazolate frameworks (HIF) HIF-1 and HIF-2 (featuring 14 Zn and 14 Co atoms, respectively) to increase their yields and crystallinity, we found that HIF-1 is generated in two different frameworks, named as HIF-1a and HIF-1b. HIF-1b is isostructural to HIF-2. We determined the gas sorption and magnetic properties of HIF-2. In comparison to HIF-1a (Brunauer-Emmett-Teller (BET) surface area of 471m(2) g(-1)), HIF-2 possesses overall very low gas sorption uptake capacities [BET(CO2) surface area=85m(2) g(-1)]. Variable temperature magnetic susceptibility measurement of HIF-2 showed antiferromagnetic exchange interactions between the cobalt(II) high-spin centres at lower temperature. Theoretical analysis by density functional theory confirmed this finding. The UV/Vis-reflection spectra of HIF-1 (mixture of HIF-1a and b), HIF-2 and HIF-3 (with 14 Cd atoms) were measured and showed a characteristic absorption band centered at 340nm, which was indicative for differences in the imidazolate framework.
KW  - Gas-sorption
KW  - Ligand design
KW  - Magnetic properties
KW  - Supramolecular chemistry
KW  - Solvothermal synthesis
Y1  - 2019
U6  - https://doi.org/10.1007/s10847-019-00926-6
SN  - 1388-3127
SN  - 1573-1111
VL  - 94
IS  - 3-4
SP  - 155
EP  - 165
PB  - Springer
CY  - Dordrecht
ER  -