A THEORETICAL STUDY ABOUT THE ELECTRONIC COOPERATIVE EFFECT ON HYDROCYANIDE CHAINS USING DFT CALCULATIONS AND AIM TOPOLOGICAL PARAMETERS
Abstract
A theoretical investigation about the cooperative effect on (HCN)n homo and (HCN)n ⋯ HF heterochains was performed in terms of structural parameters and topological properties obtained in concordance with the protocol of Bader's atoms in molecules theory. Initially, the hydrogen bonding distances, electronic densities, and Laplacian descriptors were used to characterize small (HCN)n and (HCN)n ⋯ HF chains formed by n = 2–4 units of HCN. Hydrogen bond distances and distribution of charge density have revealed that the cooperative effect on (HCN)n ⋯ HF heterochains is ruled by the polarity of the extreme hydrofluoric acid species. Furthermore, we investigated larger homo and heterochain systems formed by n = 2–8 molecules of HCN. In this insight, the drastic polarized effect caused by HF molecule which was considered very substantial at prior, in fact is seriously limited by an excessive number of HCN molecules connected to the heterochain. This leads to a stabilization of the (N ⋯ HF) hydrogen bonds with invariable electronic density in the range of 
. In this stage and henceforth, the cooperative effect is re-established with n = 4 molecules of HCN. Thereby, the electronic density of the hydrogen bonds become unaltered within the (HCN)n ⋯ HF heterochains.
