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11.
12.
3,3-Dimethyl-1-(3-methyl-1-phenylpyrazol-5-onylidene-4)-1,2,3,4-tetrahydroisoquinoline has been synthesized and its crystalline and molecular structures determined. It was found by IR and electronic absorption spectroscopic methods that the structure of this compound is not changed in solutions.  相似文献   
13.
A copper(II) valerate complex with nicotinamide (L) [CuL2(C4H9COO)2] (I) has been synthesized and studied by IR spectroscopy and thermogravimetry. The crystal structure has been determined. The crystals of 1 are monoclinic, a = 11.297(1) Å, b = 6.666(1) Å, c = 16.873(2) Å, b = 108.50(1)°, V = 1204.9(3) Å3, Z = 2, space group P21/c. The structural units of the crystal of I are centrosymmetric tetragonal bipyramidal (4+2) complex molecules. The equatorial positions of the bipyramid are occupied by trans-arranged pairs of O (Cu-O, 1.973 Å) and N (Cu-N, 2.006 Å) atoms, and the axial positions are occupied by the second O atoms of the valerate anions located at longer distances (Cu-O, 2.506 Å). The supramolecular associates formed in the crystal are layers of hydrogen-bonded complexes. The disordered hydrocarbon “tails” of the valerate groups point toward the interlayer space.  相似文献   
14.
Cage organometallosiloxanes were synthesized according to a new procedure using monomeric organoalkoxysilanes as the starting compounds. The latter were subjected to hydrolysis immediately before the exchange reaction of sodium silanolate with metal halides. Difficultly accessible metallovinylsiloxanes, metallomethylsiloxanes, and metallosiloxanes containing a functional group in the organic radical at the silicon atom can be readily prepared according to the method proposed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2530–2532, December, 1998.  相似文献   
15.
Methods of (19F, 1H) NMR and impedance spectroscopy are used to investigate the internal mobility and ionic conduction in solid solutions arising in the system PbF2-ZrF4 and polycrystals KSnZrF7, Li(Na)(NH4)6Zr4F23, and M2ZrF6 (M = K, NH4). Factors responsible for the form of ionic motions and their energetics at 170–550 K are considered. It is established that the phase transitions in these compounds are connected with the crystal transition to a superionic state and that the high ionic (superionic) conductivity of beta phases is due to the diffusion of fluoride ions, ammonium cations, and possibly alkali metal cations. The obtained data testify to a substantial role of chainlike aggregation of anionic groupings and a variableness of structural mechanisms of formation of such chains in fluorozirconates for the development of translational diffusion in these compounds.__________Translated from Elektrokhimiya, Vol. 41, No. 5, 2005, pp. 573–582.Original Russian Text Copyright © 2005 by Kavun, Uvarov, Slobodyuk, Goncharuk, Kotenkov, Tkachenko, Gerasimenko, Sergienko.  相似文献   
16.
The zeolite IPC-3, isomorphous with germanate zeolite ASU-16, and its silicon, aluminum, and titanium analogs, were obtained in the presence of 1,6-diaminohexane as a template. It is possible to incorporate selectively the elements in different crystallographic positions, determined by the nature of the element, particularly its valency and its coordination number with respect to oxygen. Silicon takes tetrahedral positions in the IPC-3 lattice, Al either tetrahedral or octahedral positions, and Ti octahedral positions. Small amounts of the lithium cations facilitate tetrahedral coordination and increase the Al content in IPC-3. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 4, pp. 246–251, July–August, 2006.  相似文献   
17.
Heating of a solution of pentaphenylantimony in toluene in atmospheric oxygen affords -oxo-bis(tetraphenylantimony) (I) in a 63% yield. The latter compound can be converted to bis(tetraphenylantimony) carbonate or phthalate by the action of carbon dioxide or phthalic anhydride, respectively. According to X-ray diffraction data, the antimony atoms in compound Ihave a distorted trigonal-bipyramidal coordination (Sb–O 2.0050(4) Å, the SbOSb angle 151.71(9)°). The molecule of bis(tetraphenylantimony) phthalate is composed of two equal fragments, and its Sb atoms also have trigonal-bipyramidal coordination (Sb–O 2.2421(8) Å; Sb–C 2.176(1), 2.115(1), 2.130(1), and 2.137(1) Å).  相似文献   
18.
Complexes of Fe(III) and Cu(II) chlorides with 2-(3,3,-dimethyl-1,2,3,4-tetrahydroisoquinolylidene-1)-5,5-dimethyl-2,3,5,6-tetrahydroimidazo[2,1-a]isoquinoline-3-one (L) were synthesized and studied by IR and electronic absorption spectroscopy. X-ray diffraction analysis of compound L was carried out. The molecule of L was found to crystallize in the form of cis-isomer with the proton localized on the nitrogen atom of the dihydroisoquinoline fragment.  相似文献   
19.
Dynamics of octahedral ions in crystal compounds MM′AF6 (M, M′=Li, Na, K, Rb, Cs; A=Ge, Ti) has been studied in the temperature range 115–500 K. Types of inner motions of complex ions have been established, and their activation energies have been estimated. First-order transition has been found in compound LiRbTiF6. Institute of Chemistry, Far-East Branch, Russian Academy of Sciences. Translated fromZhurmal Strukturnoi Khimii, Vol. 36, No. 4, pp. 697–702, July–August, 1995. Translated by L. Smolina  相似文献   
20.
The mobility of fluoride and ammonium ions (180–480 K) in compounds K2? n (NH4)nZrF6 (0.2 ≤ n ≤ 1.70) was investigated by 19F and 1H NMR. Correlations have been found between the composition of the cation sublattice, the character of ion motions, and phase transition temperature in these compounds. The hightemperature modifications with n ≥ 0.85 of the compounds are characterized by translational diffusion of fluoride and ammonium ions and by uniaxial anisotropy of the 19F magnetic shielding tensor. The electrophysical characteristics of these compounds were studied in the temperature range 300–480 K.  相似文献   
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