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61.
The First Vanadium(III) Borophosphate: Synthesis and Crystal Structure of CsV3(H2O)2[B2P4O16(OH)4] CsV3(H2O)2[B2P4O16(OH)4] was prepared under mild hydrothermal conditions (T = 165 °C) from mixtures of CsOH(aq), VCl3, H3BO3, and H3PO4 (molar ratio 1 : 1 : 1 : 2). The crystal structure was determined by X‐ray single crystal methods (monoclinic; space group C2/m, No. 12): a = 958.82(15) pm, b = 1840.8(4) pm, c = 503.49(3) pm; β = 110.675(4)°; Z = 2. The anionic partial structure contains oligomeric units [BP2O8(OH)2]5–, which are built up by a central BO2(OH)2 tetrahedron and two PO4 tetrahedra sharing common corners. VIII is octahedrally coordinated by oxygen of adjacent phosphate tetrahedra and OH groups of borate tetrahedra as well as oxygen of phosphate tetrahedra and H2O molecules, respectively (coordination octahedra VO4(OH)2 and VO4(H2O)2). The oxidation state +3 for vanadium was confirmed by measurements of the magnetic susceptibility. The trimeric borophosphate groups are connected via vanadium centres to form layers with octahedra‐tetrahedra ring systems, which are likewise linked via VIII‐coordination octahedra. Overall, a three‐dimensional framework constructed from VO4(OH)2 and VO4(H2O)2 octahedra as well as BO2(OH)2 and PO4 tetrahedra results. The structure contains channels running along [001], which are occupied by Cs+ in a distorted octahedral coordination (CsO4(H2O)2). 相似文献
62.
Two novel borophosphates, MII(C4H12N2)[B2P3O12(OH)] (MII = Co, Zn), exhibiting open frameworks, have been synthesized by hydrothermal reactions (T = 165 °C). The crystal structures of the isotypic compounds have been determined both at 293 K (orthorhombic, Ima2 (no. 46), Z = 4; MII = Co: a = 12.4635(4) Å, b = 9.4021(4) Å, c = 11.4513(5) Å, V = 1341.90 Å3, R1 = 0.0202, wR2 = 0.0452, 2225 observed reflections with I > 2σ(I); MII = Zn: a = 12.4110(9) Å, b = 9.4550(5) Å, c = 11.4592(4) Å, V = 1344.69 Å3, R1 = 0.0621, wR2 = 0.0926, 1497 observed reflections with I > 2σ(I)). Distorted CoO6‐octahedra and ZnO5‐square‐pyramids, respectively, share common oxygen‐corners with BO4‐, PO4‐ and (HO)PO3‐tetrahedra. The tetrahedral groups are linked via common corners to form infinite loop‐branched borophosphate chains [B2P3O12(OH)4–]. The open framework of MII‐coordination polyhedra and tetrahedral borophosphate chains contains a three‐dimensional system of interconnected structural channels running along [100], [011] and [011], respectively, which are occupied by di‐protonated piperazinium ions. 相似文献
63.
M. Schmidt B. Ewald Yu. Prots R. Cardoso‐Gil M. Armbrüster I. Loa L. Zhang Ya‐Xi Huang U. Schwarz R. Kniep 《无机化学与普通化学杂志》2004,630(5):655-662
Single crystals of BPO4 were grown by chemical transport reactions with PCl5 using a gradient from 1073 K to 973 K as well as with solvothermal syntheses in the temperature range between 413 K and 523 K using water, ethanol or 2‐propanol as polar protic solvents. The atomic arrangement of BPO4 was reinvestigated by means of single crystal X‐ray diffraction data and confirmed the earlier findings with significantly smaller standard deviations. Thermogravimetric investigations of powdered samples which show no extra lines in X‐ray diffraction diagrams revealed weight decrements which are attributed to water losses. The presence of protonated borate and phosphate species in a number of X‐ray pure solvothermally grown BPO4 samples is evidenced by infrared spectroscopy. 相似文献
64.
65.
Paul Simon Dirk Zahn Hannes Lichte Rüdiger Kniep 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2006,118(12):1945-1949
66.
Enkhtsetseg Dashjav Guido Kreiner Walter Schnelle Frank R. Wagner Ruediger Kniep Wolfgang Jeitschko 《ChemInform》2007,38(51):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. 相似文献
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69.
N. Jansen D. Walcher P. Gütlich D. Häußinger B. Hannebauer R. Kniep K. Lutar P. C. Schmidt D. Sellmann B. Žemva 《Il Nuovo Cimento D》1996,18(2-3):231-235
Summary Using the possibility to produce61Co sources at the MAinz MIcrotron,61Ni M?ssbauer spectroscopy was applied to different kinds of chemical problems. Measurements of isomer shifts andV
zz
values in some common compounds and compounds with unusual chemical bonding for comparison with band structure calculations,
measurement of61Ni M?ssbauer parameters in model compounds for hydrogenase and dehydrogenase with an active [NiS4] centre, and study of novel binary NiF3 compounds at helium temperature are presented.
Paper presented at ICAME-95, Rimini, 10–16 September 1995. 相似文献
70.