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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.
- 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)°.
- ItemUltrafast structural changes in SrTiO3 due to a superconducting phase transition in a YBa2Cu3O7 top layer(College Park, MD : Institute of Physics Publishing, 2010) Lübcke, A.; Zamponi, F.; Loetzsch, R.; Kämpfer, T.; Uschmann, I.; Große, V.; Schmidl, F.; Köttig, T.; Thürk, M.; Schwoerer, H.; Förster, E.; Seidel, P.; Sauerbrey, R.We investigate the structural response of SrTiO3 when Cooper pairs are broken in an epitaxially grown YBa2Cu3O 7 top layer due to both heating and optical excitation. The crystal structure is investigated by static, temperaturedependent and time-resolved x-ray diffraction. In the static case, a large strain field in SrTiO3 is formed in the proximity of the onset of the superconducting phase in the top layer, suggesting a relationship between both effects. For the time-dependent studies, we likewise find a large fraction of the probed volume of the SrTiO3 substrate strained if the top layer is superconducting. Upon optical breaking of Cooper pairs, the observed width of the rocking curve is reduced and its position is slightly shifted towards smaller angles. The dynamical theory of x-ray diffraction is used to model the measured rocking curves. We find that the thickness of the strained layer is reduced by about 200 nm on a sub-ps to ps timescale, but the strain value at the interface between SrTiO3 and YBa2Cu3O7 remains unaffected. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
- 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.
- ItemAdvances in group-III-nitride photodetectors(Sharjah [u.a.] : Bentham Open, 2010) Rivera, C.; Pereiro, J.; Navarro, A.; Muñoz, E.; Brandt, O.; Grahn, H.T.Group-III nitrides are considered to be a strategic technology for the development of ultraviolet photodetectors due to their remarkable properties in terms of spectral selectivity, radiation hardness, and noise. The potential advantages of these materials were initially obscured by their large density of intrinsic defects. The advances were thus associated in general with improvements in material quality. Although technology still also needs improvement, efforts are being intensified in the fabrication of advanced structures for photodetector applications. In particular, this review discusses the recent progress in group-III-nitride photodetectors, emphasizing the work reported on quantum-well-based photodetectors, the use of novel structures exploiting the effect of piezoelectric polarization-induced fields, and polarization-sensitive photodetectors. Furthermore, some ideas can be generalized to other material systems such as ZnO and their related compounds, which exhibit the same crystal structure as group-III nitrides. © Rivera et al.; Licensee Bentham Open.
- ItemCrystal structure of samarium-strontium-calcium orthoaluminotantalate, (Sm0.40Sr0.50Ca0.10)(Al0.70Ta 0.30)O3(Berlin : de Gruyter, 2010) Gesing, T.M.; Uecker, R.; Zheng, W.; Buhl, J.-C.Al2.90Ca0.45O12Sm 1.59Sr2Ta1.10, tetragonal, I4 (no. 82), a = 5.4174(8) Å, c = 7.643(2) Å, V = 224.3 Å3, Z = 1, Rgt(F) = 0.039, wRref(F 2) = 0.1258 , T = 298 K. © 2014 Oldenbourg Wissenschaftsverlag, München.