搜索到8篇“ HETEROBORANES“的相关文章
DFT Predictions on Structures and Stabilities of Eleven-vertex nido- and closo-Heteroboranes
2009年
Based on the octadecahedron of eleven-vertex closo-borane, the eleven-vertex closo-heteroborane was suggested with nonmetallic atoms instead of the different nonequivalent boron, and the stabilities were predicted at G96PW91/6-31+G(3d,2p) level. The small heteroatoms, C, N, O, preferentially occupy vertex 2 with the absolutely lowest relative energy to form the high stabilization closo-heteroboranes. They cap four-membered rings to satisfy the geometrical demand of short B--Z bonds. The electron attractions from the vicinal boron atoms make the frameworks shrink. Differently, Si and Ge preferentially substitute for boron at vertex 1 with six tight B--Z bonds and form stabilized molecules. P, As, S, and Se tend to occupy vertex 4 and the optimized structures belong to the nido configura- tions. In contrast to high electronegative heteroatoms, S and Se transfer less negative charges to framework and the electropositive heteroatoms, Si and Ge transfer more negative charges to framework to form the delocalization structures. The HOMO-LUMO gaps show that most of predicted clusters possess chemical stabilities. The substitutions of heteroatoms for boron atoms in eleven-vertex closo-heteroboranes are consistent with the topological charge stabilization rule proposed by Gimarc.
LI Ping
十顶点闭式杂硼烷结构的密度泛函研究被引量:2
2007年
运用G96PW91/6-31+G(3d,2p)方法研究十顶点闭式杂硼烷及其位置异构体的稳定性,为实验合成提供理论预测。就原子半径、电负性等对构型稳定性的影响,杂原子占据a和e位形成的位置异构体的稳定性差异等问题,进行稳定化能、几何构型、NBO原子电荷等的比较,得出了有意义的结论。原子半径小的杂原子易占据a位,形成的杂硼烷稳定性高。电负性大的原子有较强的吸引电子能力,与多个原子的结合能力减弱,价电子离域的能力降低,使三维芳香性降低,稳定性降低。杂原子占据的位置不同,形成产物的结构不同,稳定性也不同。1-PB9H10和1-AsB9H10的稳定性分别低于2-PB9H10和2-AsB9H10。相反地,1-SB9H9和1-SeB9H9的稳定性分别高于2-SB9H9和2-SeB9H9。部分杂硼烷的X-H键呈弱酸性,其余氢原子的反应活性也增加,使其容易结合其他基团形成衍生物。
李平
关键词:位置异构体几何构型
确定硼烷和杂硼烷价成键轨道对称性的拓扑方法被引量:1
1992年
本文通过对硼烷的分子轨道的定域化分析,建立了由硼烷或杂硼烷的骨架多面体的几何性质,确定其价成键轨道对称性的拓扑方法。从以多面体骨架的三角面和缺顶点周围的边为基约化出的不可约表示中,按建议的能量与节面数的对应规则,选定出分子的价成键轨道所属的不可约表示。
李前树唐敖庆
关键词:硼烷对称性
过渡金属杂硼烷结构规则的量子化学计算
1986年
用EHMO量子化学计算方法,计算了过渡金属杂硼烷骨架Fe_(n)B_(6-n)(n=0,1,…,6),验证和讨论了过渡金属杂硼烷的价成键和价非键轨道数BMO+NBMO=4n_(1)+9n_(2)-F。其中n_(1)、n_(2)和F都只与骨架的几何性质有关。
李志儒李前树唐敖庆
关键词:量子化学计算过渡金属BMOEHMO
稠合型硼烷、稠合型其他硼烷和稠合型过渡金属簇合物的电子需求
稠合型硼烷和稠合型其他硼烷的价电子数可用下式计算
金成树
关键词:BORANESHETEROBORANES
文献传递
Structural features of several heteroborane complexes of divalent platinum. Crystal structure of the product of the thermal treatment of 9-bi
An x-ray diffaction investigation of the product (I) of the thermal treatment of the complex 9-(PPh/sub 3/)/su...
Kukina, G A;Sergienko, V S;Porai-Koshits, M A
Structural features of several heteroborane complexes of divalent platinum. Crystal structures of 9-bis(triphenylphosphine)-6-carbodecaborane
An x-ray diffraction investigation of carborane complexes of Pt(2+) with the general formula 9-(PPh/sub 3/)/su...
Kukina, G A;Porai-Koshits, M A;Sergienko, V S;Zefirov, Yu V;Sadikov, G G
1,2-Dimethyl-1,2-Disila-Closo-Dodecaborane(12), A Silicon Analog of an Ortho-Carborane: Synthesis; X-ray Crystal Structure; NMR, Vibrational
The reaction of (CH3)2Si(NMe2)2 with BlOH14 Yields a polymer, BlOH12.Me2NSi(CH3)2NMe2n, whose pyrolysis in a s...
Seyferth, D.;Buechner, K. D.;Rees, W. S.;Wesemann, L.;Davis, W. M.

相关作者

金成树
作品数:42被引量:31H指数:3
供职机构:绥化学院
研究主题:过渡金属簇合物 簇合物 硼烷 综合化学实验 有机化学实验