Theoretical study of HCN and HNC neutral and charged clusters

M. SANCHEZ, P. F. PROVASI, G. A. AUCAR, I. ALKORTA AND J. ELGUERO

JOURNAL OF PHYSICAL CHEMISTRY B

ACS

Año: 2005 vol. 109 p. 18189 - 18194

1089-5647

A theoretica study of linear and cyclic clustersof (HCN) and (HNC) (up to n=10) has been carried out by means of DFT and MP2 ab initio methods. The transition states linking the cyclic clusters show high energetic barriers that prevent the spontaneous transformation of the high-energy clusters, (HNC) , into the low-energy ones, (HCN) . The effect of the protonation/deprotonation of the linear clusters has also been explored. The results show that (HNC) clusters with n values larger than six are thermodynamically more stable as charged systems than as neutral ones. The geometrical results have been analyzed using a Steiner-Libach plot. The electron density and its Laplacian at the bond critical points correlate with the corresponding bonds distances by means of two exponential functions, one for the open shell and another for the closed shell cases.