TY  - JOUR
A1  - Farra, Ramzi
A1  - Thiel, Kerstin
A1  - Winter, Alette
A1  - Klamroth, Tillmann
A1  - Poeppl, Andreas
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
A1  - Strauch, Peter
T1  - Tetrahalidocuprates(II)-structure and EPR spectroscopy Part 1: Tetrabromidocuprates(II)
JF  - New journal of chemistry
N2  - Tetrahalidocuprates(II) show a high degree of structural flexibility. We present the results of crystallographic and electron paramagnetic resonance (EPR) spectroscopic analyses of four new tetrabromidocuprate(II) compounds and compare the results with previously reported data. The cations in the new compounds are the sterically demanding benzyltriphenylphosphonium, methyltriphenylphosphonium, tetraphenylphosphonium, and hexadecyltrimethylammonium ions; they were used to achieve a reasonable separation of the paramagnetic Cu(II) ions for EPR spectroscopy. X-Ray crystallography shows that in all four complexes the [CuBr4](2-) units have a distorted tetrahedral coordination geometry which is in agreement with DFT calculations. The EPR hyperfine structure was not resolved. This is due to the exchange broadening resulting from still incomplete separation of the paramagnetic Cu(II) centres. Nevertheless, the principal values of the electron Zeemann tensor (g(parallel to) and g(perpendicular to)) of the complexes could be determined. A correlation of structural (X-ray) parameters with the spin density at the copper centres (DFT) is well reflected in the EPR spectra of the bromidocuprates. This enables the correlation of X-ray and EPR parameters to predict the structure of tetrabromidocuprates in physical states other than the crystalline state. As a result, we provide a method to structurally characterize [CuBr4](2-) in, for example, ionic liquids or in solution, which has important implications for e.g. catalysis or materials science.
Y1  - 2011
U6  - https://doi.org/10.1039/c1nj20271e
SN  - 1144-0546
VL  - 35
IS  - 12
SP  - 2793
EP  - 2803
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Winter, Alette
A1  - Thiel, Kerstin
A1  - Zabel, Andre
A1  - Klamroth, Tillmann
A1  - Poeppl, Andreas
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
A1  - Strauch, Peter
T1  - Tetrahalidocuprates(II) - structure and EPR spectroscopy. Part 2: tetrachloridocuprates(II)
JF  - New journal of chemistry
N2  - 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(parallel to) and g(perpendicular to), 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.
Y1  - 2014
U6  - https://doi.org/10.1039/c3nj01039b
SN  - 1144-0546
SN  - 1369-9261
VL  - 38
IS  - 3
SP  - 1019
EP  - 1030
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - GEN
A1  - Winter, Alette
A1  - Thiel, Kerstin
A1  - Zabel, André
A1  - Klamroth, Tillmann
A1  - Pöppl, Andreas
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
A1  - Strauch, Peter
T1  - Tetrahalidocuprates(II) – structure and EPR spectroscopy
BT  - Part 2: tetrachloridocuprates(II)
N2  - 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.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 240 
KW  - electron-spin resonance
KW  - liquid-crystal precursors
KW  - copper(II) halide salts
KW  - ionic liquid
KW  - square planar
KW  - tetrachlorocuprate(II) salts
KW  - molecular-structure
KW  - magnetic-properties
KW  - paramagnetic-resonance
KW  - temperature phase
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-95012
SP  - 1019
EP  - 1030
ER  - 
TY  - JOUR
A1  - Zehbe, Kerstin
A1  - Kollosche, Matthias
A1  - Lardong, Sebastian
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
T1  - Ionogels Based on Poly(methyl methacrylate) and Metal-Containing Ionic Liquids: Correlation between Structure and Mechanical and Electrical Properties
JF  - International journal of molecular sciences
N2  - Ionogels (IGs) based on poly(methyl methacrylate) (PMMA) and the metal-containing ionic liquids (ILs) bis-1-butyl-3-methlimidazolium tetrachloridocuprate(II), tetrachloride cobaltate(II), and tetrachlorido manganate(II) have been synthesized and their mechanical and electrical properties have been correlated with their microstructure. Unlike many previous examples, the current IGs show a decreasing stability in stress-strain experiments on increasing IL fractions. The conductivities of the current IGs are lower than those observed in similar examples in the literature. Both effects are caused by a two-phase structure with micrometer-sized IL-rich domains homogeneously dispersed an IL-deficient continuous PMMA phase. This study demonstrates that the IL-polymer miscibility and the morphology of the IGs are key parameters to control the (macroscopic) properties of IGs.
KW  - microstructure
KW  - ionogels
KW  - ionic liquids
KW  - phase separation
KW  - mechanical properties
KW  - ionic conductivity
Y1  - 2016
U6  - https://doi.org/10.3390/ijms17030391
SN  - 1422-0067
VL  - 17
PB  - MDPI
CY  - Basel
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  - GEN
A1  - Zehbe, Kerstin
A1  - Kollosche, Matthias
A1  - Lardong, Sebastian
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
T1  - Ionogels based on poly(methyl methacrylate) and metal-containing ionic liquids
BT  - correlation between structure and mechanical and electrical properties
N2  - Ionogels (IGs) based on poly(methyl methacrylate) (PMMA) and the metal-containing ionic liquids (ILs) bis-1-butyl-3-methlimidazolium tetrachloridocuprate(II), tetrachloride cobaltate(II), and tetrachlorido manganate(II) have been synthesized and their mechanical and electrical properties have been correlated with their microstructure. Unlike many previous examples, the current IGs show a decreasing stability in stress-strain experiments on increasing IL fractions. The conductivities of the current IGs are lower than those observed in similar examples in the literature. Both effects are caused by a two-phase structure with micrometer-sized IL-rich domains homogeneously dispersed an IL-deficient continuous PMMA phase. This study demonstrates that the IL-polymer miscibility and the morphology of the IGs are key parameters to control the (macroscopic) properties of IGs.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 361 
KW  - microstructure
KW  - ionogels
KW  - ionic liquids
KW  - phase separation
KW  - mechanical properties
KW  - ionic conductivity
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400607
ER  - 
TY  - JOUR
A1  - Abouserie, Ahed
A1  - Zehbe, Kerstin
A1  - Metzner, Philipp
A1  - Kelling, Alexandra
A1  - Günter, Christina
A1  - Schilde, Uwe
A1  - Strauch, Peter
A1  - Körzdörfer, Thomas
A1  - Taubert, Andreas
T1  - Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
JF  - European journal of inorganic chemistry : a journal of ChemPubSoc Europe
N2  - Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
KW  - Ionic liquids
KW  - Alkylpyridinium salts
KW  - Structure elucidation
KW  - Phase transitions
Y1  - 2017
U6  - https://doi.org/10.1002/ejic.201700826
SN  - 1434-1948
SN  - 1099-0682
SP  - 5640
EP  - 5649
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Abouserie, Ahed
A1  - Zehbe, Kerstin
A1  - Metzner, Philipp
A1  - Kelling, Alexandra
A1  - Günter, Christina
A1  - Schilde, Uwe
A1  - Strauch, Peter
A1  - Körzdörfer, Thomas
A1  - Taubert, Andreas
T1  - Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
JF  - European journal of inorganic chemistry : a journal of ChemPubSoc Europe
N2  - Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
KW  - Ionic liquids
KW  - Alkylpyridinium salts
KW  - Structure elucidation
KW  - Phase transitions
Y1  - 2017
U6  - https://doi.org/10.1002/ejic.201700826
SN  - 1434-1948
SN  - 1099-0682
SP  - 5640
EP  - 5649
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Bhattacharyya, Biswajit
A1  - Balischewski, Christian
A1  - Sperlich, Eric
A1  - Günter, Christina
A1  - Mies, Stefan
A1  - Kelling, Alexandra
A1  - Taubert, Andreas
T1  - N-Butyl Pyridinium Diiodido Argentate(I)
BT  - A One-Dimensional Ag-I Network with Superior Solid-State Ionic Conductivity at Room Temperature
T2  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - A new solid-state material, N-butyl pyridinium diiodido argentate(I), is synthesized using a simple and effective one-pot approach. In the solid state, the compound exhibits 1D ([AgI2](-))(n) chains that are stabilized by the N-butyl pyridinium cation. The 1D structure is further manifested by the formation of long, needle-like crystals, as revealed from electron microscopy. As the general composition is derived from metal halide-based ionic liquids, the compound has a low melting point of 100-101 degrees C, as confirmed by differential scanning calorimetry. Most importantly, the compound has a conductivity of 10(-6) S cm(-1) at room temperature. At higher temperatures the conductivity increases and reaches to 10(-4 )S cm(-1) at 70 degrees C. In contrast to AgI, however, the current material has a highly anisotropic 1D arrangement of the ionic domains. This provides direct and tuneable access to fast and anisotropic ionic conduction. The material is thus a significant step forward beyond current ion conductors and a highly promising prototype for the rational design of highly conductive ionic solid-state conductors for battery or solar cell applications.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1341 
KW  - AgI
KW  - ionic conductivity
KW  - Ionic liquids
KW  - thermal properties
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-604874
SN  - 1866-8372
IS  - 1341
ER  - 
TY  - JOUR
A1  - Bhattacharyya, Biswajit
A1  - Balischewski, Christian
A1  - Sperlich, Eric
A1  - Günter, Christina
A1  - Mies, Stefan
A1  - Kelling, Alexandra
A1  - Taubert, Andreas
T1  - N-Butyl Pyridinium Diiodido Argentate(I)
BT  - A One-Dimensional Ag-I Network with Superior Solid-State Ionic Conductivity at Room Temperature
JF  - Advanced materials interfaces
N2  - A new solid-state material, N-butyl pyridinium diiodido argentate(I), is synthesized using a simple and effective one-pot approach. In the solid state, the compound exhibits 1D ([AgI2](-))(n) chains that are stabilized by the N-butyl pyridinium cation. The 1D structure is further manifested by the formation of long, needle-like crystals, as revealed from electron microscopy. As the general composition is derived from metal halide-based ionic liquids, the compound has a low melting point of 100-101 degrees C, as confirmed by differential scanning calorimetry. Most importantly, the compound has a conductivity of 10(-6) S cm(-1) at room temperature. At higher temperatures the conductivity increases and reaches to 10(-4 )S cm(-1) at 70 degrees C. In contrast to AgI, however, the current material has a highly anisotropic 1D arrangement of the ionic domains. This provides direct and tuneable access to fast and anisotropic ionic conduction. The material is thus a significant step forward beyond current ion conductors and a highly promising prototype for the rational design of highly conductive ionic solid-state conductors for battery or solar cell applications.
KW  - AgI
KW  - ionic conductivity
KW  - Ionic liquids
KW  - thermal properties
Y1  - 2023
U6  - https://doi.org/10.1002/admi.202202363
SN  - 2196-7350
VL  - 10
IS  - 12
PB  - Wiley
CY  - Hoboken
ER  -