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- ItemIodidobis(≠5-penta-methyl-cyclo-penta-dien-yl)titanium(III)(Chester : International Union of Crystallography, 2010) Kessler, M.; Spannenberg, A.; Rosenthal, U.In the title complex mol-ecule, [Ti(C10H15) 2I], the paramagnetic Ti(III) atom is coordinated by two penta-methyl-cyclo-penta-dienyl (Cp*) ligands and one iodide ligand. The two Cp*ligands are in a staggered orientation. The coordination geometry at the titanium atom can be described as distorted trigonal-planar.
- ItemIntermolecular hydrogen bonding in isostructural pincer complexes [OH-(t-BuPOCOPt-Bu)MCl] (M = Pd and Pt)(Chester : International Union of Crystallography, 2019) Joksch, M.; Spannenberg, A.; Beweries, T.In the crystal structure of the isostructural title compounds, namely {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridopalladium(II), [Pd(C22H39O3P2)Cl], 1, and {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridoplatinum(II), [Pt(C22H39O3P2)Cl], 2, the metal centres are coordinated in a distorted square-planar fashion by the POCOP pincer fragment and the chloride ligand. Both complexes form strong hydrogen-bonded chain structures through an interaction of the OH group in the 4-position of the aromatic POCOP backbone with the halide ligand.
- Item[2,2-Bis(diphenylphosphanyl)propane κ2P,P0] tetracarbonylchromium(0)dichloromethane monosolvate(Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, [Cr(C27H26P2)(CO) 4]·CH2Cl2, was obtained by the reaction of Ph2PCMe2PPh2 with Cr(CO)6 in refluxing toluene by substitution of two carbonyl ligands. The CrC 4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 70.27 (2)°.
- Item(+)-{1,2-Bis[(2R,5R)-2,5-diethyl-phospho-lan-1-yl]ethane- κ2 P,P′}(≠4-cyclo-octa-1,5-diene)rhodium(I) tetra-fluoridoborate(Chester : International Union of Crystallography, 2010) Schulz, S.; Fischer, C.; Drexler, H.-J.; Heller, D.The title compound, [Rh(C8H12)(C18H 36P2)]BF4, exhibits a rhodium(I) complex cation with a bidentate bis-phosphine ligand and a bidentate 2, 2-coordinated cyclo-octa-1,5-diene ligand. The ligands form a slightly distorted square-planar coordination environment for the Rh(I) atom. An intra-molecular P-Rh-P bite angle of 83.91 (2)° is observed. The dihedral angle between the P - Rh - P and the X - Rh - X planes (X is the centroid of a double bond) is 14.0 (1)°. The BF4 anion is disordered over two positions in a 0.515 (7):0.485 (7) ratio.
- Item(tert-Butylimido)bis(η5-cyclopenta-dienyl) pyridinezirconium(IV)(Chester : International Union of Crystallography, 2010) Kaleta, K.; Arndt, P.; Spannenberg, A.; Rosenthal, U.The title compound, [Zr(C5H5)2(C 4H9N)(C5H5N)], was obtained from the reaction of (C5H5)2Zr(py)(η2- Me3SiC2SiMe3) (py is pyridine) and tBuN=C=NtBu alongside the formation of (C 5H5)2Zr(CNtBu)(2-Me 3SiC2SiMe3). The zirconium atom is coordinated in a distorted tetrahedral geometry by two cyclopentadienyl ligands, a pyridine ligand, and a tertbutylimido ligand via a Zr=N double bond. The tertbutyl group is disordered over two positions in a 0.634 (5):0.366 (5) ratio.
- Item[Bis(diphenylphosphanyl)dimethylsilane κ2P,P′] tetracarbonylchromium(0)(Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, [Cr(C26H26P2Si)(CO) 4], was obtained by the reaction of Ph2PSiMe 2PPh2 with Cr(CO)6 in refluxing toluene by ligand exchange. The CrC4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 80.27 (1)°.
- ItemLayered manganese bismuth tellurides with GeBi4Te7- and GeBi6Te10-type structures: Towards multifunctional materials(London : RSC Publ., 2019) Souchay, Daniel; Nentwig, Markus; Günther, Daniel; Keilholz, Simon; de Boor, Johannes; Zeugner, Alexander; Isaeva, Anna; Ruck, Michael; Wolter, Anja U.B.; Büchnerde, Bernd; Oeckler, OliverThe crystal structures of new layered manganese bismuth tellurides with the compositions Mn0.85(3)Bi4.10(2)Te7 and Mn0.73(4)Bi6.18(2)Te10 were determined by single-crystal X-ray diffraction, including the use of microfocused synchrotron radiation. These analyses reveal that the layered structures deviate from the idealized stoichiometry of the 12P-GeBi4Te7 (space group P3m1) and 51R-GeBi6Te10 (space group R3m) structure types they adopt. Modified compositions Mn1-xBi4+2x/3Te7 (x = 0.15-0.2) and Mn1-xBi6+2x/3Te10 (x = 0.19-0.26) assume cation vacancies and lead to homogenous bulk samples as confirmed by Rietveld refinements. Electron diffraction patterns exhibit no diffuse streaks that would indicate stacking disorder. The alternating quintuple-layer [M2Te3] and septuple-layer [M3Te4] slabs (M = mixed occupied by Bi and Mn) with 1 : 1 sequence (12P stacking) in Mn0.85Bi4.10Te7 and 2 : 1 sequence (51R stacking) in Mn0.81Bi6.13Te10 were also observed in HRTEM images. Temperature-dependent powder diffraction and differential scanning calorimetry show that the compounds are high-temperature phases, which are metastable at ambient temperature. Magnetization measurements are in accordance with a MnII oxidation state and point at predominantly ferromagnetic coupling in both compounds. The thermoelectric figures of merit of n-type conducting Mn0.85Bi4.10Te7 and Mn0.81Bi6.13Te10 reach zT = 0.25 at 375 °C and zT = 0.28 at 325 °C, respectively. Although the compounds are metastable, compact ingots exhibit still up to 80% of the main phases after thermoelectric measurements up to 400 °C. © The Royal Society of Chemistry 2019.
- ItemStatic Dielectric Constant of β-Ga2O3 Perpendicular to the Principal Planes (100), (010), and (001)(Pennington, NJ : ECS, 2019) Fiedler, A.; Schewski, R.; Galazka, Z.; Irmscher, K.The relative static dielectric constant ℇr of β-Ga2O3 perpendicular to the planes (100), (010), and (001) is determined in the temperature range from 25 K to 500 K by measuring the AC capacitance of correspondingly oriented plate capacitor structures using test frequencies of up to 1 MHz. This allows a direct quantification of the static dielectric constant and a unique direction assignment of the obtained values. At room temperature, ℇr perpendicular to the planes (100), (010), and (001) amounts to 10.2 ± 0.2, 10.87 ± 0.08, and 12.4 ± 0.4, respectively, which clearly evidence the anisotropy expected for β-Ga2O3 due to its monoclinic crystal structure. An increase of ℇr by about 0.5 with increasing temperature from 25 K to 450 K was found for all orientations. Our ℇr data resolve the inconsistencies in the previously available literature data with regard to absolute values and their directional assignment and therefore provide a reliable basis for the simulation and design of devices. © The Author(s) 2019.
- Item(+)-{1,2-Bis[(2R,5R)-2,5-dimethyl-phospho-lan-1-yl]ethane- κ2 P,P′}(η4-cyclo-octa-1,5-diene) rhodium(I) tetra-fluorido-borate(Chester : International Union of Crystallography, 2010) Schulz, S.; Drexler, H.-J.; Heller, D.The title compound, [Rh(C8H12)(C14H 28P2)]BF4, exhibits a rhodium(I) complex cation with a bidentate bis-phosphine ligand and a bidentate η2, η2-coordinated cyclo-octa-1,5-diene. Together the ligands create a slightly distorted square-planar cordination environment for the Rh(I) atom. There are three mol-ecules in the asymmetric unit and intra-molecular P - Rh - P bite angles of 82.78 (5), 82.97 (6) and 83.09 (5)° are observed. The dihedral angles between the P - Rh - P and the X - Rh - X planes (X is the centroid of a double bond) are 14.7 (1), 14.8 (1) and 15.3 (1)°. The structure exhibits disorder of one cyclo-octa-diene ligand as well as one BF4 anion.
- ItemBis(dimethyl sulfoxide)hydridobis(triphenylphosphane)cobalt(I)(Chester : International Union of Crystallography, 2010) Hapke, M.; Weding, N.; Spannenberg, A.The title compound, [CoH(C18H15P)2(C 2H6OS)2], was synthesized by the reaction of chloridotris(triphenyl-phosphane)cobalt(I), [ClCo(PPh3)3], in the presence of one equivalent potassium hydridotris(pyrazol-yl)borate in dimethyl sulfoxide. The structure displays a distorted trigonal-pyramidally coordinated cobalt(I) atom, with two phosphane ligands and one DMSO ligand in the equatorial plane. The coordination is completed by one further DMSO ligand and the anionic hydride in the axial positions.