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481.
Artem L. Gushchin Maxim N. Sokolov Pavel A. Abramov Nina F. Zakharchuk Vladimir P. Fedin 《Journal of Cluster Science》2008,19(4):659-666
Single crystals of Ta4S1.5Se7.5I8 are obtained by heating Ta, S, Se and I2 at 300 °C in 4.0:1.0:8.0:4.4 molar ratio. The structure was determined by X-ray analysis and consists of molecular clusters [Ta4(μ4-S)(μ2-QaxSeeq)4I8] (Q ≈ Se0.87S0.13). The tantalum atoms form a square with long Ta…Ta distances (3.26–3.32 Å), with four dichalcogenide ligands bridging the Ta–Ta edges and a sulfur atom capping the square. Each Ta atom has two terminal iodine atoms. Raman spectroscopy study shows the presence of the characteristic absorption band at 396 cm?1 which is due to the Ta4–μ4-S vibrations. Cyclic voltammetry shows that Ta4S1.5Se7.5I8 in solid state undergoes quasi-reversible one-electron oxidation which is metal-centered. 相似文献
482.
Bykov M. V. Abramov Z. D. Orlov T. S. Pakhomova M. V. Borodina T. N. Smirnov V. I. Suslov D. S. 《Journal of Structural Chemistry》2021,62(8):1218-1228
Journal of Structural Chemistry - Reaction of Pd(acac)2 with BF3·OEt2 in the presence of tri(2-furyl)phosphine in toluene yields complex [Pd(acac)(TFP)2]BF4 (I) (TFP is tri(2-furyl)phosphine)... 相似文献
483.
484.
采用溶胶-凝胶法分别在K9玻璃、单晶硅和石英玻璃基底上制备了纳米TiO2和SiO2薄膜。利用SEM、UV-Vis及反射式椭圆偏振光谱仪对薄膜的微观结构及光学特性进行了表征和分析。结果表明:3种基底中, 单晶硅基底上TiO2和SiO2薄膜折射率最大;在非晶态K9玻璃和石英玻璃基底上TiO2薄膜折射率和透光率差异较大;SiO2薄膜在非晶态基底上折射率、透光率相近;3种基底上薄膜的折射率和消光系数都有随波长增大而减小的趋势, 同时Cauchy模型能较好的描述单晶硅基底上两种薄膜在400~800 nm波段的光学性能。 相似文献
485.
Yu. L. Frolov A. V. Abramov N. N. Chipanina T. N. Aksamentova M. G. Voronkov 《Journal of Structural Chemistry》1999,40(6):849-854
Pentacoordinated silicon compounds of the series 4-XC6H4C(O)O(CH2)mSi(CH3)3-nFn (m = 1, 2; n= 1,2,3) with an intramolecular 0→Si bond are studied by ab initia and semiempirical (AMI) quantum chemical methods.
The results are compared with published experimental data. The C6H5C(O)OCH2SiF3 molecule is calculated in an RHF approximation using the 6–31G*basis set. The total energy of the molecule for its geometry
optimization is calculated by the MP2 method including electron correlation. This leads to considerably improved agreement
between the calculated coordination energy (25.3 kJ/mole) and the experimental value (28.5 kJ/mole). The geometry and the
dipole moment calculated by both ab initio (HF/6-31G*//HF/6-31G*, MP2/6-31G*//MP2/6-31G*) methods and by the AMI method are
in satisfactory agreement with the experimental data. 相似文献
486.
487.
A. V. Anyushin P. A. Abramov Nikolay B. Kompankov M. N. Sokolov V. P. Fedin 《Russian Journal of Coordination Chemistry》2013,39(1):77-81
Reaction of NiCl2 · 6H2O and P(CH2OH)3 (THP) with H2S and (H7O3)2[Mo6Cl14] · 3H2O in ethanol produces new trinuclear nickel sulphide complex [Ni3(μ3-S)2{(HOCH2)2PCH2OP(CH2OH)2}3][Mo6Cl14] · 0.8H2O (I) with new bidentate phosphine-phosphinite ligand resulted from THP condensation. It was characterized by X-ray structure analysis. 相似文献
488.
Artem L. Gushchin Maxim N. Sokolov Pavel A. Abramov Nina F. Zakharchuk Vladimir P. Fedin 《Journal of Cluster Science》2009,20(1):241-248
Single crystals of Ta4S1.5Se7.5I8 are obtained by heating Ta, S, Se and I2 at 300 °C in 4.0:1.0:8.0:4.4 molar ratio. The structure was determined by X-ray analysis and consists of molecular clusters [Ta4(μ4-S)(μ2-QaxSeeq)4I8] (Q ≈ Se0.87S0.13). The tantalum atoms form a square with long Ta…Ta distances (3.26–3.32 Å), with four dichalcogenide ligands bridging the Ta–Ta edges and a sulfur atom capping the square. Each Ta atom has two terminal iodine atoms. Raman spectroscopy study shows the presence of the characteristic absorption band at 396 cm?1 which is due to the Ta4–μ4-S vibrations. Cyclic voltammetry shows that Ta4S1.5Se7.5I8 in solid state undergoes quasi-reversible one-electron oxidation which is metal-centered. 相似文献
489.
490.
采用溶胶-凝胶法分别在K9玻璃、单晶硅和石英玻璃基底上制备了纳米TiO2和SiO2薄膜。利用SEM、UV-Vis及反射式椭圆偏振光谱仪对薄膜的微观结构及光学特性进行了表征和分析。结果表明:3种基底中, 单晶硅基底上TiO2和SiO2薄膜折射率最大;在非晶态K9玻璃和石英玻璃基底上TiO2薄膜折射率和透光率差异较大;SiO2薄膜在非晶态基底上折射率、透光率相近;3种基底上薄膜的折射率和消光系数都有随波长增大而减小的趋势, 同时Cauchy模型能较好的描述单晶硅基底上两种薄膜在400~800 nm波段的光学性能。 相似文献