中国科学B辑(英文版)
中國科學B輯(英文版)
중국과학B집(영문판)
SCIENCE IN CHINA(SCIENTIA SINICA)
2003年
4期
361-370
,共10页
廖新丽%吴玮%莫亦荣%张乾二
廖新麗%吳瑋%莫亦榮%張乾二
료신려%오위%막역영%장건이
HCN%HNC%isomerization%VB theory%bonding feature
Within the bonded tableau unitary group approach (BTUGA), a scheme, combined with Pauling's resonance theory to select the predominant valence bond structures for VB calculations, is proposed. This scheme ensures a reliable and illustrative bonding picture in the description of chemical reactions, as exemplified by the isomerization reaction HNCHCN. The computation results account for important bonding features about this isomerization at the ab initio level and explore the mechanism of phenomena such as (i) HCN is more stable than HNC; (ii) the C-N bond first lengthens and then shortens in the vicinity of the transition state; (iii) only H-atom migration is observed in the isomerization process, without the breaking of the CN bond. Our results demonstrate that only a few bonded tableau functions are sufficient enough to provide a visual and reliable bonding picture.