Science in China Series B: Chemistry

, Volume 46, Issue 4, pp 361–370 | Cite as

VB studies on bonding features of HNC↔HCN



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 HNC↔HCN. 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.


HCN HNC isomerization VB theory bonding feature 


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© Science in China Press 2003

Authors and Affiliations

  1. 1.Department of Chemistry, State Key Laboratory for Physical Chemistry of Solid Surfaces, Center for Theoretical ChemistryXiamen UniversityXiamenChina

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