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881.
[{Y(OH)(Benzo-15-Crown-5)(CH3CN)}2]I4, a Salt with a Dimeric Hydroxide-Bridged out-of-cavity Complex Coulorless single crystals of [{Y(OH)(Benzo-15-Crown-5)(CH3CN)}2]I4 are obtained from the reaction of YI3 and benzo-15-crown-5 in acetonitrile. The crystal structure (monoclinic, P21/c, Z = 2, a = 1198.1(1), b = 1375.9(2), c = 1623.5(2) pm, β = 106.50(1)° R1 = 0.0843, wR2 = 0.2193 contains the hydroxide-bridged cationic out-of-cavity dimer. 相似文献
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Wolfgang Einholz Knut Vaas Christoph Wieloch Bernd Speiser Tina Wizemann Markus Strbele Hans‐Jürgen Meyer 《无机化学与普通化学杂志》2002,628(1):258-268
Chemical and Cyclovoltammetric Investigation of the Redoxreactions of the Decahalodecaborates closo ‐[B10X10]2– and hypercloso ‐[B10X10]· – (X = Cl, Br)1). Crystal Structure Analysis of Cs2[B10Br10] · 2 H2O The oxidation of the decachloro‐closo‐decaborates(2–) Cs2[B10Cl10] or [Me4N]2[B10Cl10] with Tl(CF3COO)3 leads to the corresponding radical monoanion hypercloso‐[B10Cl10] · –, which was characterized by ESR and UV/Vis spectroscopy. [B10Cl10] · – does not dimerize like [B10H10] · – but it is reduced by acetonitrile to the dianion [B10Cl10]2–. Cs2[B10Cl10] reacts with stronger oxidation agents like CoF3 (in dichloromethane) or XeF2 (in perfluorhexane), respectively, to yield B9Cl9 and, in traces, B8Cl8. In opposite to this, the decabromoderivative Cs2[B10Br10] does not show any reaction with Tl(CF3COO)3 in acetonitrile or with CoF3 in CH2Cl2. The oxidation of the dianions [B10X10]2– (X = Cl, Br) was studied by electroanalytical methods (cyclic voltammetry, chronoamperometry, chronocoulometry). Formal potentials were determined for the two steps of the reaction, which do not seem to be affected by structural rearrangements. The crystal structure of Cs2[B10Br10] · 2 H2O was analyzed by single‐crystal X‐ray diffraction. Cs2[B10Br10] · 2 H2O crystallizes monoclinic (space group I2/a, (no. 15), Z = 8, a = 1361.54(9) pm, b = 1215.89(5) pm, c = 3108.4(2) pm, α = 90°, β = 97.916(8)°, γ = 90°). The closo‐cluster B10Br102– has a bicapped square antiprismatic structure with idealized D4d symmetry. 相似文献
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NbOCl3 was obtained from a reaction of NbCl5 and Nb2O5 at 260?C. Contrary to the literature data, NbOCl3 crystallizes in the non‐centrosymmetric space group P&4macr;21m as determined by single‐crystal and powder X‐ray diffraction data (crystal: a = b = 1089.59(6) pm, c = 394.79(2) pm, Z = 4, R1 = 0.0229, wR2 = 0.0459, powder: a = b = 1086.36(6) pm, c = 393.65(2) pm). The niobium atoms are surrounded by distorted octahedra built of four chlorine atoms and two oxygen atoms in trans positions. Two such octahedra are edge‐bridged through shared chlorine atoms, forming dimers. These units are linked to each other by apical oxygen atoms forming one‐dimensional Nb2Cl6O2 chains parallel [001]. Contrary to the literature data two different Nb‐O distances are obtained. 相似文献
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Production and Decomposition of (NH4)[BF4] and H3N‐BF3 (NH4)[BF4] is produced as single crystals during the reaction of elemental boron and NH4HF2 (B : NH4HF2 = 1 : 2) and NH4F (B : NH4F = 1 : 4), respectively, in sealed copper ampoules at 300 °C. The crystal structure (baryte type, orthorhombic, Pnma, Z = 4) was redetermined at ambient temperature (a = 909.73(18), b = 569.77(10), c = 729.47(11) pm, Rall = 0.0361) and at 140 K (a = 887.3(2), b = 574.59(12), c = 717.10(12) pm, Rall = 0.0321). Isolated (NH4)+ and [BF4]— tetrahedra are the important building units. The thermal behaviour of (NH4)[BF4] was investigated under inert (Ar, N2) and reactive conditions (NH3) with the aid of DTA/TG and DSC measurements and with in‐situ X‐ray powder diffraction as well. Finally, (NH4)[BF4] is decomposed yielding NH3 and BF3, BN is not produced under the current conditions. Colourless single crystals of H3N‐BF3 were prepared directly from the components NH3 and BF3. The crystal structure was determined anew at 293 and 170 K (orthorhombic, Pbca, Z = 8, a = 815.12(10), b = 805.91(14), c = 929.03(12) pm, Rall = 0.0367; a = 807.26(13), b = 800.48(10), c = 924.31(11) pm, Rall = 0.0292, T = 170 K). The crystal structure contains isolated molecules H3N‐BF3 in staggered conformation with a B‐N distance of 158 pm. The thermal behaviour of H3N‐BF3 was studied likewise. 相似文献
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Ternary Halides of the A3MX6 Type. VIII On the Crystal Structure of Li3InCl6 Colorless single crystals of Li3InCl6 are obtained from a 3 : 1 molar mixture of LiCl and InCl3 via Bridgman‐type crystal growth. The crystal structure (monoclinic, C2/m, Z = 2, a = 643.2(3), b = 1109.3(3), c = 639.8(3) pm, β = 109.8(1)° R1 = 0.0549, wR2 = 0.1364 (all data) may be derived from the AlCl3‐type of structure as was previously also found for the bromides Li3MBr6 (M = Sm–Lu, Y) and iodides Li3MI6 (M = Er–Yb, Y). 相似文献