Structure and dissociation of cyanogen halides BrCN and ICN

Structural properties and dissociation of cyanogen bromide BrCN, cyanogen iodide ICN, and their isomers have been studied in detail using ab initio MP2, CCSD, and CCSD(T) methods. After dissociation of BrCN and ICN, the fragmented atoms have been considered to be either in their ground state or in their valence excited states. The recent experimental value for the strength of the CN bond of CN radical has been compared with our value calculated from the dissociation of BrCN. Interesting results have been obtained when BrCN and ICN dissociated to atoms that are in their valence excited states. The structural properties of BrCN and ICN and dissociation energy of BrCN agree very well with the theoretical and experimental values wherever available. The dissociation pathways of ICN are first predicted. The isomerization energy of BrCN is compared with the existing theoretical result. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010