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Idan Avigdori Dr. Alla Pogoreltsev Dr. Alexander Kaushanski Dr. Natalia Fridman Prof. Dr. Mark Gandelman 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23682-23685
N-heterocyclic nitrogen Lewis acids are a recent addition to the field of organic chemistry. Based on nitrenium cations, these acids where previously shown to generate Lewis adducts when combined with the appropriate Lewis bases. Herein, a triazinium-based Lewis acid was combined with tBu3P to generate a frustrated Lewis pair (FLP) capable of cleaving, for the first time, Si−H bonds in silanes. Whereas low yields were initially encountered owing to insufficient Lewis acidity, a new nitrenium-based Lewis acid was synthesized, and its superior Lewis acidity was experimentally and computationally confirmed. A FLP based on this acid cleaved the Si−H bond in PhSiH3, generating the triazane product in a quantitative yield. This unprecedented N−H triazane was fully characterized by multinuclear NMR techniques and single-crystal X-ray crystallography. A new class of compounds, N-H triazanes display the potential capacity to participate in hydride transfer reactions. 相似文献
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V. L. Matukhin V. N. Anashkin A. I. Pogoreltsev I. A. Safin 《Applied magnetic resonance》1992,3(3-4):711-728
Nuclear quadrupole resonance (NQR) of63Cu has been performed to study the electronic and magnetic properties of YBa2Cu3O6.1 ceramics, treated in iodine or bromine vapours. An analysis of the NQR shows undistorted CuO2 planes and the absence of an increase of the oxygen content in chains of Cu(1)-O in halogen treated Y-Ba-Cu-O ceramics.139La NQR spin-lattice relaxation measurements in powdered La2?x CuO4?y compounds are also reported. The present results indicate that the139La nuclear relaxation is dominated by the Cu++-Cu++ magnetic correlations. 相似文献
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E. V. Bogdanov E. I. Pogoreltsev S. V. Mel’nikova M. V. Gorev I. N. Flerov M. S. Molokeev A. V. Kartashev A. G. Kocharova N. M. Laptash 《Physics of the Solid State》2013,55(2):409-418
Thermal, physical, structural, optical, and dielectric investigations have been performed for oxyfluoride solid solutions (NH4)2W1 — x Mo x O2F4 (x = 0, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1). The character of the influence of the chemical and hydrostatic pressures on the stability of the parent (space group Cmcm) and distorted ferroelastic and antiferroelectric phases has been determined by analyzing the temperature-pressure, unit cell volume-composition, and temperature-composition phase diagrams. The specific features of the nature and mechanism of the phase transitions have been discussed using the available data on the structural, entropy, and dielectric parameters. 相似文献
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Bogdanov E. V. Pogoreltsev E. I. Gorev M. V. Molokeev M. S. Flerov I. N. 《Physics of the Solid State》2019,61(2):192-200
Physics of the Solid State - The crystals of (ND4)3VO2F4 with a high degree of deuteration (~87%) have been grown and a significant (~1.5%) increase in the unit cell volume has been detected. The... 相似文献
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Valentina D. Fokina Mikhail V. Gorev Alla G. Kocharova Evgenii I. Pogoreltsev Igor N. Flerov 《Solid State Sciences》2009,11(4):836-840
Calorimetric measurements performed in a wide temperature range on (NH4)3VO2F4 have shown the presence of four heat capacity anomalies at T1 = 438 K, T2 = 244 K, T3 = 210.2 K, T4 = 205.1 K associated with the first order phase transitions. In accordance with the permittivity behavior, the structural transformations are of nonferroelectric nature. Pressure dependence of the phase transition temperatures has been studied by DTA under pressure. The entropy of phase transitions is analyzed mainly in the framework of the orientational disordering of NH4+ and VO2F43? ions in a cubic phase. 相似文献
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I. N. Flerov M. S. Molokeev N. M. Laptash A. A. Udovenko E. I. Pogoreltsev S. V. Mel'nikova S. V. Misyul 《ChemInform》2015,46(49):no-no
Single crystals of (NH4)3SnF7 are obtained from aqueous solutions of (NH4)2SnF6 and excess NH4F during solvent evaporation. 相似文献
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V. L. Matukhin A. I. Pogoreltsev V. N. Anashkin I. A. Safin L. E. Matukhina Ya. A. Ossipyan N. S. Sidorov V. I. Kulakov 《Applied magnetic resonance》1998,14(4):559-566
We have investigated the low-temperature behavior of Cu NQR for iodinated RBa2Cu3O x (R = Y, Gd) compounds. The different influence of Gd spins on the Cu(1) and Cu(2) sites was used to separate the contributions of both sites in the spectra. The distinct NQR lines associated with the different oxygen-coordinated Cu(1) sites have been observed. The NQR spectra of the Cu(1) sites show that the iodine treatment gives rise to the modifications of the oxygen sublattice. From the analysis of the NQR spectra of the Cu(1) sites follows an increase of the average length of the Cu(1)-O chains at treatment. 相似文献
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Bogdanov E. V. Pogoreltsev E. I. Kartashev A. V. Gorev M. V. Molokeev M. S. Mel’nikova S. V. Flerov I. N. Laptash N. M. 《Physics of the Solid State》2020,62(7):1271-1279
Physics of the Solid State - The (NH4)3VOF5 crystals have been synthesized and their homogeneity and single-phase structure has been established by the X-ray diffraction, energy dispersive... 相似文献