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1.
The complexes [Et2NH2] 3 + [BiCl6]3? (I), [NH4]+[BiI4(C5H5N)2]?·2C5H5N (II), [Ph3MeP] 2 + [BiI5]2? (III), [Ph3MeP] 2 + [BiI5(C5H5N)]2?·C5H5N (IV), [Ph3MeP] 3 + [Bi3I12]3? (V), [Ph3(i-Pr)P] 3 + [Bi3I12]3?·2Me2C=O (VI), [Ph3BuP] 2 + [Bi2I8·2Me2C=O]2? (VII), and [Ph3BuP] 2 + [Bi2I8·2Me2S=O]2? (VIII) were obtained by reactions of bismuth iodide with ammonium and phosphonium iodides in acetone, pyridine, or dimethyl sulfoxide.  相似文献   
2.
The reaction of the pentaphenyphosphorus solvate Ph5P·1/2PhH (I) with carboxylic and sulfonic acids was used to synthesize tetraphenylphosphonium carboxylates Ph4POC(O)R, R = C6H4(2-OH) (II), C6H4 (2-COOH) (III), H (IV), Me (V), CCl3 (VI), Ph (VII), PhCH=CH (VIII), CH2CH2C(O)OH (IX), CH=CHC(O) OH(X), and CH2C(O)OH (XI) and tetraphenylphosphonium sulfonates Ph4POSO2Ar, Ar = Ph (XII), C6H4Me4 (XIII), and C6H3(-COOH)(4-OH) (XIV). Compound XII was also prepared from compound I and SO3 in benzene. According to X-ray diffraction data, the crystals of I contain two types of crystallographically independent molecules with a slightly distorted trigonal-bipyramidal configuration [Ia, CaxPCax 178.44(8)°, P- Cax 1.985(2), 1.987(2) Å, P-Ceq 1.854(2), 1.846(2), 1.840(2) Å; Ib, CaxPCax 178.45(9)°, P-Cax 1.980(2), 1.975 (2) Å, P-Ceq 1.840(2), 1.846(2), 1.854(2) Å]. In the cations of compounds II, III and XIV, the coordination of the phosphorus atom is tetrahedral [CPC angle: II, 106.2(2)?111.6(1)°; III, 104.01(6)?113.03(6)°; XIV, 107.54 (6)?112.79(6)°]; the anions contain intramolecular O-H?O hydrogen bonds between the hydroxyl hydrogen atom and carboxyl oxygen atom (II, 1.34; III, 1.23; and XIV, 1.83 Å).  相似文献   
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4.
The MNDO method was used to study the potential energy surface for Zn$n and ZnnXm (n = 2 – 4) linear zinc clusters with terminal and lateral coordinations of the X acceptor groups. The results agree with the formerly proposed hypothesis on the modes of Hg cluster stabilization. Possible effects of the individual properties of the element and the value of the acceptor strength of the ligands on the relative stability of the clusters are discussed.  相似文献   
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6.
Corrections to the neutrino magnetic dipole moment from the singly charged Higgs bosons h (±) and $\tilde \delta ^{\left( \pm \right)}$ were calculated within the left-right symmetric model involving Majorana neutrinos. It is shown that, if the h (±) and $\tilde \delta ^{\left( \pm \right)}$ bosons lie at the electroweak scale, the contributions from Higgs sector are commensurate with the contribution of charged gauge bosons or may even exceed it. The behavior of the neutrino flux inmatter and in amagnetic field was studied. It was found that resonance transitions between light and heavy neutrinos are forbidden.  相似文献   
7.
The reactions of formation and decay of defect-impurity complexes in solids are investigated theoretically on the basis of the generalized Liouville equation in phase space. The use of this equation (instead of the diffusion equation ordinarily used) yields an expression for the total rate constants of the reaction of complex formation which correctly takes into account both factors limiting the reaction rate in the general case: the diffusional mobility of the constituents and the energy barrier of the reaction. A comparison is made with the Waite theory, which is based on the diffusion equation and takes into account the presence of an energy barrier for the reaction by means of a radiation boundary condition on a reaction sphere. It is shown that the Waite method of taking the energy barrier into account leads to a systematic and substantial underestimate of the barrier-limited part of the total rate constant of the reaction. The possibility of generalizing the theory developed in this paper to the case of reactions which can involve not only atoms and defects but also the charge carriers in semiconductors (electrons and holes) is discussed. Zh. Tekh. Fiz. 67, 33–38 (November 1997)  相似文献   
8.
Dichloro(methyl)(vinyl)silane reacts with DMSO in the presence of octamethyltrisiloxane to form cyclooligomethyl(vinyl)siloxanes(MeViSiO) n (n = 3-6). The reaction involves disproportionation of octamethyltrisiloxane into hexamethyldisiloxane and decamethyltetrasiloxane. Along with the latter two products, insertion products of methyl vinyl silanone into both permethyloligosiloxanes were identified. Alkyltrichlorosilanes RSiCl3 (R = Me, Et) react with DMSO in the presence of octamethyltrisiloxane to form cyclic oligoalkyltrichlorosiloxanes (RClSiO) m (m = 3-6).  相似文献   
9.
The complexes [Ph3PMe] 2 + [BiI5]2? (I) and [Ph3PMe] 2 + [BiI5 · C 5H5N]2? · C 5H5N (II) were synthesized by the reaction of bismuth triiodide with triphenylmethylphosphonium iodide, and their structures were determined by X-ray diffraction analysis. The P atom in cation I has slightly distorted tetragonal coordination polyhedron (the CPC angles 109.42(4)° and 109.52(4)°, the bond lengths P-CPh 1.779(2), P-CMe 1.793(1) Å. The Bi atom in the anion of complex I has an ideal trigonal-bipyramidal coordination polyhedron (Bi-Ieq 3.0031(4), Bi-Ieq 3.0485(5) Å). The crystal of complex II consists of the anions [BiI5 · C 5H5N]2?, solvated pyridine molecules, and two types of crystallographically independent tetrahedral triphenylmethylphosphonium cations (the angles CPC 106.9(1)°–111.7(1)°, the distances P-CPh 1.785(3)–1.792(3), P-CMe 1.793(3), 1.786(3) Å). The Bi atoms in the anion of complex II have a distorted octahedral coordination polyhedron (Bi-I 3.0878(4)–3.1240(3), Bi-N(1) 2.628(3) Å).  相似文献   
10.
Complexes [Ph3MeP] 2 + [BiI3.5Br1.5(C5H5N)]2? · C5H5N(I), [Ph4Bi] 4 + [Bi4I16]4? · 2Me2C=O (II), and [Ph3(iso-Am)P] 4 + [Bi8I28]4? · 2Me2C=O (III) were synthesized by reactions of bismuth iodide with triphenylmethylphosphonium bromide, triphenylbismuthonium sulfosalicylate, and triphenylisoamylphosphonium iodide, respectively. The crystal structures of complexes I–III were determined by X-ray crystallography. The complexes contain, in addition to cations and solvent molecules, mono-, tetra-, and octanuclear anions, in which bismuth atoms are in octahedral coordination.  相似文献   
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