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- ItemMethyl 5-chloro-2-hydr-oxy-3-(4-methoxyphenyl)-4,6-dimethylbenzoate(Chester : International Union of Crystallography, 2009) Adeel, M.; Ali, I.; Langer, P.; Villinger, A.In the title compound, C17H17ClO4, the dihedral angle between the mean planes of the two benzene rings is 65.92 (5)°. The methyl ester group lies within the ring plane [deviations of O atoms from the plane = -0.051 (2) and 0.151 (2) Å] due to an intra-molecular O - H⋯O hydrogen bond. In the crystal, molecules are held together by rather weak non-classical inter-molecular C - H⋯O hydrogen bonds, resulting in dimeric units about inversion centers, forming eight- and ten-membered ring systems as R22(8) and R2 2(10) motifs. © Adeel et al. 2009.
- Item[1-Dimethylsilyl-2-phenyl-3-(η5-tetramethylcyclopentadienyl) prop-1-en-1-ylκC1](n5-pentamethylcyclopentadienyl)- titanium(III)(Chester : International Union of Crystallography, 2009) Lamač, M.; Spannenberg, A.; Arndt, P.; Rosenthal, U.The title compound, [Ti(C10H15)(C20H 26Si)], was obtained from the reaction of [Ti{5: 1-C5Me4(CH2)}(5-C 5Me5)] with the alkynylsilane PhC2SiMe 2H. The complex crystallizes with two independent mol-ecules in the asymmetric unit, which differ in the conformation of the propenyl unit, resulting in their having opposite helicity. No inter-molecular inter-actions or inter-actions involving the Si- H bond are present. The observed geometrical parameters are unexceptional compared to known structures of the same type.
- ItemRedetermination of EuScO3(Chester : International Union of Crystallography, 2009) Kahlenberg, V.; Maier, D.; Veličkov, B.Single crystals of europium(III) scandate(III), with ideal formula EuScO3, were grown from the melt using the micro-pulling-down method. The title compound crystallizes in an ortho-rhom-bic distorted perovskite-type structure, where Eu occupies the eightfold coordinated A sites (site symmetry m) and Sc resides on the centres of corner-sharing [ScO6] octa-hedra (B sites with site symmetry ). The structure of EuScO3 has been reported previously based on powder diffraction data [Liferovich & Mitchell (2004). J. Solid State Chem. 177, 2188-2197]. The results of the current redetermination based on single-crystal diffraction data shows an improvement in the precision of the structral and geometric parameters and reveals a defect-type structure. Site-occupancy refinements indicate an Eu deficiency on the A site coupled with O defects on one of the two O-atom positions. The crystallochemical formula of the investigated sample may thus be written as A(0.032Eu0.968)BScO2.952.
- 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.
- ItemTris(η5-cyclopentadienyl)hafnium(III)(Chester : International Union of Crystallography, 2011) Burlakov, V.V.; Arndt, P.; Spannenberg, A.; Rosenthal, U.In the crystal structure of the title compound, [Hf(C5H 5)3], three cyclopentadienyl ligands surround the Hf III atom in a trigonal-planar geometry. The molecule lies on a sixfold inversion axis.
- ItemEthyl 4-chloro-2′-fluoro-3-hydroxy-5-methylbiphenyl-2-carboxylate(Chester : International Union of Crystallography, 2011) Adeel, M.; Langer, P.; Villinger, A.In the title compound, C 16H 14ClFO 3, the dihedral angle between the mean planes of the two benzene rings is 71.50 (5)°. Due to an intramolecular O - H⋯O hydrogen bond between the hydroxy group and the carbonyl O atom of the ethyl ester group, the ethyl ester group lies within the ring plane. The crystal structure is consolidated by intermolecular C - H⋯O and C - H⋯F interactions.
- Item(μ5-Cyclo-penta-dien-yl)bis-(triphenyl-phosphane)cobalt(I) -toluene-n-hexane (1/0.20/0.25)(Chester : International Union of Crystallography, 2008) Hapke, M.; Spannenberg, A.The title compound, [Co(C5H5)(C18H15P)2]·0.2C7H8·0.25C6H14, was synthesized by the reaction of cobaltocene, Cp2Co, with elemental lithium in tetra-hydro-furan in the presence of two equivalents of PPh3. The mol-ecular structure displays a cobalt(I) center in a distorted trigonal-planar coordination environment, with one Cp and two phosphane ligands. There are two crystallographically independent mol-ecules in the asymmetric unit besides the disordered solvent molecules.
- 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)°.
- ItemRedetermination of terbium scandate, revealing a defect-type perovskite derivative(Chester : International Union of Crystallography, 2008) Veličkov, B.; Kahlenberg, V.; Bertram, R.; Uecker, R.The crystal structure of terbium(III) scandate(III), with ideal formula TbScO3, has been reported previously on the basis of powder diffraction data [Liferovich & Mitchell (2004). J. Solid State Chem. 177, 2188-2197]. The current data were obtained from single crystals grown by the Czochralski method and show an improvement in the precision of the geometric parameters. Moreover, inductively coupled plasma optical emission spectrometry studies resulted in a nonstoichiometric composition of the title compound. Site-occupancy refinements based on diffraction data support the idea of a Tb deficiency on the A site (inducing O defects on the O2 position). The crystallochemical formula of the investigated sample thus may be written as A(0.04Tb0.96) BScO2.94. In the title compound, Tb occupies the eightfold- coordinated sites (site symmetry m) and Sc the centres of corner-sharing [ScO6] octa-hedra (site symmetry ). The mean bond lengths and site distortions fit well into the data of the remaining lanthanoid scandates in the series from DyScO3 to NdScO3. A linear structural evolution with the size of the lanthanoid from DyScO3 to NdScO3 can be predicted.
- Item(Isopropyl-amino)(meth-yl)diphenyl-phospho-nium iodide(Chester : International Union of Crystallography, 2011) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, C 16H 21NP +· I -, was obtained by the reaction of PH 2PN( iPr)P(Ph)N( iPr)H with MeI involving cleavage of one of the P - N bonds in diethyl ether. The two phenyl rings form a dihedral angle of 82.98 (5)°. A weak donor-acceptor N - H⋯I inter-action is observed.