Density functional studies of potential energy surfaces of SiOH- HSiO and PXH⁺- HPX⁺ (X= F, Cl) systems

Abstract

Two hybrid density functionals (B3LYP and B3PW91) have been used to investigate SiOH- HSiO and PXH⁺- HPX⁺(X= F, Cl) systems. The reactions SiOH → HSiO and PXH⁺→ HPX⁺(X= F, Cl) are predicted to be endothermic. Our calculated geometries, vibrational frequencies and zero-point vibrational energies are in good agreement with the high level post-SCF studies of others.

Inclusion of electron correlation decreases the activation energies. Our predicted activation energies and reaction energies are in good agreement with the results of other estimates. Our predicted ESR hyperfine coupling constants of HSiO are in good agreement with the results of experiment. The Si-O bond is predicted to be non-covalent for all the stationary points of Si-OH-HSiO system. The P-X ( X= F, Cl) bond is predicted to be non-covalent for all the stationary points of PXH⁺- HPX⁺(X= F, Cl) systems except for HPCl⁺ and the transition state of the reaction PClH⁺→ HPCl⁺.