46089
2017
2017
eng
5640
5649
10
article
Wiley-VCH
Weinheim
1
--
--
--
Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
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.
European journal of inorganic chemistry : a journal of ChemPubSoc Europe
10.1002/ejic.201700826
1434-1948
1099-0682
wos:2017
WOS:000418925900003
Taubert, A (reprint author), Univ Potsdam, Inst Chem, D-14476 Potsdam, Germany., ataubert@uni-potsdam.de
Deutsche Forschungsgemeinschaft (DFG) SPP1708 Grant [TA571/13-1]; University of Potsdam
importub
2020-04-19T22:34:01+00:00
filename=package.tar
fbfabf8f6bfc7c2f01dc87e268ac2b03
Ahed Abouserie
Kerstin Zehbe
Philipp Metzner
Alexandra Kelling
Christina Günter
Uwe Schilde
Peter Strauch
Thomas Körzdörfer
Andreas Taubert
eng
uncontrolled
Ionic liquids
eng
uncontrolled
Alkylpyridinium salts
eng
uncontrolled
Structure elucidation
eng
uncontrolled
Phase transitions
Institut für Chemie
Institut für Geowissenschaften
Referiert
Institut für Erd- und Umweltwissenschaften
Import
45922
2017
2017
eng
5640
5649
10
article
Wiley-VCH
Weinheim
1
--
--
--
Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
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.
European journal of inorganic chemistry : a journal of ChemPubSoc Europe
10.1002/ejic.201700826
1434-1948
1099-0682
wos:2017
WOS:000418925900003
Taubert, A (reprint author), Univ Potsdam, Inst Chem, D-14476 Potsdam, Germany., ataubert@uni-potsdam.de
Deutsche Forschungsgemeinschaft (DFG) SPP1708 Grant [TA571/13-1]; University of Potsdam
importub
2020-03-24T18:34:10+00:00
filename=package.tar
00392e77f607fcfeee5c17ec027a6884
Ahed Abouserie
Kerstin Zehbe
Philipp Metzner
Alexandra Kelling
Christina Günter
Uwe Schilde
Peter Strauch
Thomas Körzdörfer
Andreas Taubert
eng
uncontrolled
Ionic liquids
eng
uncontrolled
Alkylpyridinium salts
eng
uncontrolled
Structure elucidation
eng
uncontrolled
Phase transitions
Institut für Chemie
Institut für Geowissenschaften
Referiert
Institut für Erd- und Umweltwissenschaften
Import
32047
2010
2010
eng
article
1
--
--
--
On the chemical synthesis of titanium nanoparticles from ionic liquids
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.
http://www.springerlink.com/content/101572
10.1007/s00706-010-0403-4
0026-9247
allegro:1991-2014
10108401
Monatshefte fuer Chemie. - ISSN 0026-9247. - 141 (2010), 12, S. 1273 - 1278
Ayi A. Ayi
Varsha Khare
Peter Strauch
Jèrôme Girard
Katharina M. Fromm
Andreas Taubert
Institut für Chemie
Referiert
36330
2012
2012
eng
9046
9051
6
18
22
article
Royal Society of Chemistry
Cambridge
1
--
--
--
Highly structured, biomorphous beta-SiC with high specific surface area from Equisetaceae
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.
Journal of materials chemistry
10.1039/c2jm30253e
0959-9428
wos:2011-2013
WOS:000302634800042
Strauch, P (reprint author), Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany.
University of Potsdam
Mike Neumann
Robert Noeske
Andreas Taubert
Brigitte Tiersch
Peter Strauch
Institut für Chemie
Referiert
37095
2011
2011
eng
2793
2803
11
12
35
article
Royal Society of Chemistry
Cambridge
1
--
--
--
Tetrahalidocuprates(II)-structure and EPR spectroscopy Part 1: Tetrabromidocuprates(II)
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.
New journal of chemistry
10.1039/c1nj20271e
1144-0546
wos:2011-2013
WOS:000297222300010
Strauch, P (reprint author), Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany., pstrauch@uni-potsdam.de
Ministry of Higher Education of Syria; German Research Council;
University of Potsdam; MPI of Colloids and Interfaces (Colloid Chemistry
Department)
Ramzi Farra
Kerstin Thiel
Alette Winter
Tillmann Klamroth
Andreas Poeppl
Alexandra Kelling
Uwe Schilde
Andreas Taubert
Peter Strauch
Institut für Chemie
Referiert
37230
2011
2011
eng
13537
13543
7
30
13
article
Royal Society of Chemistry
Cambridge
1
--
--
--
On the interaction of ascorbic acid and the tetrachlorocuprate ion [CuCl4](2-) in CuCl nanoplatelet formation from an ionic liquid precursor (ILP)
The formation of CuCl nanoplatelets from the ionic liquid precursor (ILP) butylpyridinium tetrachlorocuprate [C4Py](2)[CuCl4] using ascorbic acid as a reducing agent was investigated. In particular, electron paramagnetic resonance (EPR) spectroscopy was used to evaluate the interaction between ascorbic acid and the Cu(II) ion before reduction to Cu(I). EPR spectroscopy suggests that the [CuCl4](2-) ion in the neat IL is a distorted tetrahedron, consistent with DFT calculations. Addition of ascorbic acid leads to the removal of one chloride from the [CuCl4](2-) anion, as shown by DFT and the loss of symmetry by EPR. DFT furthermore suggests that the most stable adduct is formed when only one hydroxyl group of the ascorbic acid coordinates to the Cu(II) ion.
Physical chemistry, chemical physics : a journal of European Chemical Societies
10.1039/c1cp20648f
1463-9076
wos:2011-2013
WOS:000292978300009
Taubert, A (reprint author), Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25,Bldg 26, D-14476 Golm, Germany., ataubert@uni-potsdam.de
University of Potsdam; MPI of Colloids and Interfaces (Colloid Chemistry
Department)
Kerstin Thiel
Tillmann Klamroth
Peter Strauch
Andreas Taubert
Institut für Chemie
Referiert
38321
2014
2014
eng
1019
1030
12
3
38
article
Royal Society of Chemistry
Cambridge
1
--
--
--
Tetrahalidocuprates(II) - structure and EPR spectroscopy. Part 2: tetrachloridocuprates(II)
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.
New journal of chemistry
10.1039/c3nj01039b
1144-0546
1369-9261
wos:2014
WOS:000331805000023
Strauch, P (reprint author), Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany., pstrauch@uni-potsdam.de
Alette Winter
Kerstin Thiel
Andre Zabel
Tillmann Klamroth
Andreas Poeppl
Alexandra Kelling
Uwe Schilde
Andreas Taubert
Peter Strauch
Institut für Chemie
Referiert
9501
2013
2013
eng
1019
1030
postprint
1
--
2013-11-29
--
Tetrahalidocuprates(II) – structure and EPR spectroscopy
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.
Part 2: tetrachloridocuprates(II)
urn:nbn:de:kobv:517-opus4-95012
online registration
New J. Chem. (2014) Nr. 38, S. 1019-1030. - DOI: 10.1039/C3NJ01039B
Keine öffentliche Lizenz: Unter Urheberrechtsschutz
Alette Winter
Kerstin Thiel
André Zabel
Tillmann Klamroth
Andreas Pöppl
Alexandra Kelling
Uwe Schilde
Andreas Taubert
Peter Strauch
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
240
eng
uncontrolled
electron-spin resonance
eng
uncontrolled
liquid-crystal precursors
eng
uncontrolled
copper(II) halide salts
eng
uncontrolled
ionic liquid
eng
uncontrolled
square planar
eng
uncontrolled
tetrachlorocuprate(II) salts
eng
uncontrolled
molecular-structure
eng
uncontrolled
magnetic-properties
eng
uncontrolled
paramagnetic-resonance
eng
uncontrolled
temperature phase
Chemie und zugeordnete Wissenschaften
open_access
Institut für Chemie
Referiert
Open Access
Universität Potsdam
https://publishup.uni-potsdam.de/files/9501/pmnr240_online.pdf