A5042797967- Crystal Structures and Properties
- Chemical Synthesis and Characterization
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Inorganic Chemistry and Materials
- Polyoxometalates: Synthesis and Applications
- Luminescence Properties of Advanced Materials
- Catalysis and Oxidation Reactions
- Thermal and Kinetic Analysis
- Nuclear materials and radiation effects
- Radioactive element chemistry and processing
- Organometallic Compounds Synthesis and Characterization
- Advanced Condensed Matter Physics
- Magnetism in coordination complexes
- Metal-Organic Frameworks: Synthesis and Applications
- Transition Metal Oxide Nanomaterials
- Iron-based superconductors research
- Solid-state spectroscopy and crystallography
- Crystal structures of chemical compounds
- Lanthanide and Transition Metal Complexes
- Rare-earth and actinide compounds
- Inorganic Fluorides and Related Compounds
- Pigment Synthesis and Properties
- Metal complexes synthesis and properties
- Catalytic Processes in Materials Science
University of Bonn
2015-2024
Institute of Inorganic Chemistry of the Slovak Academy of Sciences
2007-2020
Ludwig-Maximilians-Universität München
2008-2012
Universität Innsbruck
2009-2011
University of Münster
1992-2009
University of Liège
2002
Justus-Liebig-Universität Gießen
1991-2001
Giessen School of Theology
1986-1989
Coordination or local environments (e.g., tetrahedra and octahedra) are powerful descriptors of the crystalline structure materials. These structural essential to understanding crystal chemistry design new However, extensive statistics on occurrence environment not available even common chemistries such as oxides. Here, we present first large-scale statistical analysis coordination cations in oxides using a large set experimentally observed compounds (about 8000). Using newly developed...
Going to extremes: A high-pressure borate was obtained under extreme conditions. In this species, each BO4 tetrahedron is connected a second through common edge (see structure).
Abstract Herein, the synthesis and characterization of first mixed‐valent, purely cobalt‐based zeolitic imidazolate framework, Co II 3 III 2 (C H N ) 12 is presented. The material adopts cubic garnet‐type structure combines high thermal stability up to 350 °C with excellent chemical stability. Electrochemical showed that cobalt centres are redox active efficiently support oxygen evolution, thus rendering this framework a potential candidate for single‐site heterogeneous catalysis based on...
Abstract AlB 4 O 6 N, Al 0.97 Cr 0.03 B and 0.83 0.17 N are the first representatives of recently established structure‐family oxonitridoborates containing 3+ . These compounds isotypic to CrB synthesized in a multi‐anvil press under high‐pressure/high‐temperature conditions 7.0 GPa/1350 °C. Structural refinement by single‐crystal X‐ray diffraction shows that they crystallize space group P 3 mc (no. 186) with two formula units per cell. Detailed characterization including high‐temperature...
Abstract Durch chemischen Transport mit Chlor als Transportmittel (1100°C → 1000°C) erhielten wir dunkelgrüne, gut ausgebildete Kristalle von α‐CrPO 4 . Die Substanz kristallisiert in der Raumgruppe Imma a = 10,403(2), b 12,898(2), c 6,299(1) Å. Kristallstruktur wurde aus Einkristalldaten bestimmt (R 0,038; 1481 F o , 34 Variable). ist CrO 6 ‐Oktaedern und PO ‐Tetraedern aufgebaut. Bemerkenswert sind kantenverknüpfte ‐Oktaeder‐Paare, die an gegenüberliegenden Kanten noch zwei verbunden sind....
Abstract The new borates Fe II 6 B 22 O 39 ⋅ H 2 (colourless) and Co (dichroic: red/bluish) were synthesised under the high‐pressure/high‐temperature conditions of GPa 880 °C (Fe)/950 (Co) in a Walker‐type multi‐anvil apparatus. compounds crystallise orthorhombic space group Pmn 1 ( Z =2) with lattice parameters =771.9(2), b =823.4(2), c =1768.0(4) pm, V =1.1237(4) nm 3 , R =0.0476, wR =0.0902 (all data) for =770.1(2), =817.6(2), =1746.9(4) =1.0999(4) =0.0513, =0.0939 O. structure type M...
We investigated the magnetic and structural properties of quasi-one-dimensional 3${d}^{1}$ quantum chain system TiPO${}_{4}$ ($J~$ 965 K) by susceptibility, heat capacity, electron spin resonance, x-ray diffraction, nuclear resonance (NMR) measurements, density functional theory (DFT) calculations. undergoes two magnetostructural phase transitions, one at 111 K other 74 K. Below K, NMR detects different $^{31}\mathrm{P}$ signals susceptibility vanishes, while DFT calculations evidence a bond...
The surprisingly complicated crystal structure of (bis(terpyridine))copper(II) tetraphenylborate [Cu(tpy)2](BPh4)2 (tpy = 2,2':6',2″-terpyridine) consists six crystallographically independent [Cu(tpy)2](2+) complexes. At ambient temperature, five out [Cu(II)N6] chromophores appear to be compressed octahedra, while at 100 K, four exhibit elongated and only two octahedral geometry. Temperature dependent single UV/vis (100, 298 K) EPR measurements (20, 100, as well AOM calculations suggest that...
Synthesis and use of the emblematic Wilkinson's catalyst by mechanochemistry was achieved.
Chemical transport experiments are a valuable aid of great potential in the synthesis and thermochemical characterization solids. Compounds interest can often only be crystallized by this method. The use balance allows very detailed observations, particularly course experiment over time (simultaneous or sequential deposition multiple-phase solids). computer program CVTRANS enables quantitative description based on cooperative model. A compilation recent results illustrates development...
Unter extremen Bedingungen konnte ein Hochdruckborat synthetisiert werden, in dem alle BO4-Tetraeder eine gemeinsame Kante zu einem zweiten aufweisen (siehe Strukturausschnitt).
Abstract Well‐shaped yellow to red transparent single crystals of the phosphide oxides RE ZnPO ( = Y, La–Nd, Sm, Gd, Dy, Ho) were synthesized from elements and ZnO in NaCl/KCl fluxes sealed silica ampoules. Four structures (NdZnPO type, R 3 m ) refined crystal X‐ray diffractometer data: a 388.5(2), c 3032(1) pm, wR 2 0.0380, 360 F values for YZnPO, 394.6(2), 3071(1) 0.0587, 226 SmZnPO, 392.2(2), 3056(1) 0.0262, 462 GdZnPO, 389.33(6), 3030.5(4) 0.0453, 217 DyZnPO each with 14 variables per...
Abstract The equiatomic rare earth metal zinc arsenide oxides RE ZnAsO ( = Y, La–Nd, Sm, Gd–Er) were synthesized in well crystallized form from the elements, arsenic, and ZnO NaCl/KCl fluxes sealed silica ampoules. samples characterized by powder single‐crystal X‐ray data. HoZnAsO ErZnAsO are reported for first time. Four structures (ZrCuSiAs type, space group P 4/ nmm ) refined diffractometer data: a 394.23(3), c 884.0(1) pm, wR 2 0.0345, 216 F values YZnAsO, 409.56(3), 907.0(1) 0.0502, 285...
The iron borate β -FeB 2 O 4 was synthesized under high-pressure / high-temperature conditions of 8 GPa and 1030 ◦ C. structure is isotypic to HP-NiB , representing the second example a in which every BO tetrahedron shares common edge with one. - FeB crystallizes space group C2/c (Z = 4) parameters 950.0(2), b 562.9(2), c 443.7(1) pm, 108.50(3) V 0.22495(8) nm 3 R1 0.0293, wR2 0.0647 (all data). consists layers tetrahedra, connected via strings edge-sharing FeO 6 octahedra. A ligand field...
The bulk magnetic properties of the new quasi-one-dimensional Heisenberg antiferromagnet, CuCrO${}_{4}$, were characterized by susceptibility, heat capacity, optical spectroscopy, electron paramagnetic resonance and dielectric capacitance measurements, density functional evaluations intrachain interchain spin-exchange interactions. We found type-II multiferroicity below N\'eel temperature 8.2(5) K, arising from competing antiferromagnetic nearest-neighbor (${J}_{\mathrm{nn}}$)...
Abstract Based on our newly developed microwave cavity perturbation technique, the conductivity of diverse vanadium(III), (IV), and (V) phosphate catalysts was measured under reaction conditions for selective oxidation n ‐butane. The response gas phase identified as a very sensitive measure redox kinetics, reversibility, stability samples, which are important prerequisites highly active catalysts. sensitivity achieved by method comparable to surface‐sensitive methods such X‐ray photoelectron...
γ-NiB4O7 was synthesized in a high-pressure/high-temperature experiment at 5 GPa and 900 °C. The single-crystal structure analysis yielded the following results: space group P6522 (No. 179), = 425.6(2), c 3490.5(2) pm, V 0.5475(2) nm3, Z 6, Flack parameter x −0.010(5). Second harmonic generation measurements confirmed acentric crystal structure. Furthermore, characterized via vibrational as well electronic absorption spectroscopy, magnetic measurements, high-temperature X-ray diffraction,...
The reaction network of n-butane selective oxidation was comparatively analyzed over a novel αII-V0.8W0.2OPO4 orthophosphate and reference vanadyl pyrophosphate (VPP) based catalyst via parameter field studies (T = 360–420 °C, x(n-butane) 0.5–2.0%, x(O2) 10–20%) as well cofeed pulse experiments with presumed intermediates. For VPP the selectivity to target product maleic anhydride (MAN) is particularly sensitive temperature, concentration, amount cofed H2O, whereas MAN W-containing almost...