DFT based calculation of interaction energy between metal halides and organic bases

Abstract

Interaction energy ( E int) for 324 interactions between 12 metal halides (A), and 27 organic bases (B) have been evaluated with the help of Cache software using DFT-B88-PW91 method. The halides are chloride, bromide and iodide of Sn(IV), Zn(II), Cd(II), Hg(II). The organic bases include three monosubstituted derivatives, nitrobenzene, benzamide, aniline and ortho, meta and para derivatives of eight disubstituted derivatives, which are nitro, amido, amino, cyanotoluenes and amino, cyano, amido and nitrobenzoic acids. The results indicate that acceptor strength is in the order SnCl 4 > HgCl 2 > SnBr 4 > HgBr 2 > SnI 4 > CdCl 2 > HgI 2 > ZnCl 2 > CdBr 2 > ZnBr 2 > CdI 2 > ZnI 2. The chemical potential μ A also supports the above order. Amino toluene is the strongest base, in respect of interaction, with halides of Sn(IV), Cd(II) and Hg(II), whereas amino benzoic acid is the strongest base against Zn(II) halides. Nitro toluene is the weakest base against all the acceptor-A. The base strength changes in ortho, meta and para positions. The values of interaction energy below 0.09 show weak interaction, values above 1.2 mediums, and above 2.02 strong interaction. The observation also indicates that best interaction is when global softness values, of acid and base are equal.