Ab initio molecular orbital investigation of SiOH+-XH, SiOH+-X2 and SiOH+-XY(YX) (XÂ =Â YÂ =Â F, Cl and Br) proton-bond complexes

The results of theoretical studies on structures and energetics are presented for proton-bond complexes SiOH+-XH, SiOH+-X2 and SiOH+-XY(YX) (X = Y = F, Cl and Br). In all the monocations complexes, the halogen atom shares a proton with SiO. The calculated energetic results show that the stability decreases when descending in the corresponding periodic table column. The possible proton transfer dissociation processes of SiOH+ + XH, SiOH+ + X2 and SiOH+ + XY systems into XH2+, X2H+, XYH+ and YXH+, and SiO are calculated to be endothermic. The natural bond orbital (NBO) results show that the largest intermolecular charge transfer is found in the Br bonded complexes.