Interpretation of Bond Angles in Some Hydride Molecules

Abstract

The dependence of the bond angles in the molecules XH₂ and YH₃ (X = O, S, Se and Y = N, P, As ) and related iso electronic molecular ions upon the mass of the central atom is examined. Calculations of optimized geometries are carried out by using Hartree-Fock theory and double-zeta basis sets. The results are compared with experimental and accurate computational results in order to investigate the applicability of simple valence shell electron pair repulsion and valence bond rules for geometry prediction. Particular attention is given to the valence bond picture of the effect of the size of the central atom.