甲硅硫醛(H_2SiS)脱氢反应的反应路径解析  

ERACTION ERGODOGRAPHY FOR DEHYDROGENATION OF SILATHIONE

作　　者：韩云竹[1] 杨光辉[2] 赵成大[2] 

机构地区：[1]聊城师范学院化学系 [2]东北师范大学化学系

出　　处：《物理化学学报》1990年第4期445-448,共4页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金

摘　　要：本文用内禀反应坐标(IRC)方法讨论了甲硅硫醛分子的脱氢反应机理.在RHF/4-31G基组上对此反应做了量子化学从头计算和反应路径解析,得到H_2SiS的平衡几何、过渡态结构、反应势能曲线、活化能,反应热以及沿反应坐标一些物理量的变化,并对平衡几何和过渡态做了振动分析.同时,计算了反应的频率因子A和在500K时的活化熵△S≠。The reaction mechanism for dehydrogenation of silathione H_2SiS was studied bymeans of intrinsic reaction coordinate (IRC) method. The reaction ergodography wasanalyzed by ab initio MO calculations using RHF/4-31G basis set. The equilibriumstructure of H_2SiS which has C_(2υ). symmetry was optimized.The bond lengths of Si-Sand Si-H are 2.018 A and 1.484 A, respectively. The bond angle of HSiS is125.3°. The transition state was also located which has C_3 symmetry. The bondlengths of Si-S, Si-H_1 and Si-H_2 are 2.045A, 1.860A and 1.522A, respectively.The bond angles of H_1SiS and H_2SiS are 105.0°and 147. 4°, respectively. The ac-tivation energy was calculated to be 396.4 kJ·mol^(-1) and the reaction heat is 210.0kJ·mol^(-1). The change of some physical properties along IRC were presented. At thesame time, the vibrational analyses of the reactant and the transition state have alsobeen done. At last, the frequency factor A of the reaction and the entropy of acti-vation at 500K were calculated with the application of RRKM theory. The results ofH_2SiS were compared with its carbon analogy: thioformaldehyde CH_2S.

关 键 词：甲硅硫醛 H2SiS 脱氢反应 

分 类 号：O627.41[理学—有机化学]