Ab initio study of H 2SO 4 rotamers

Abstract

This work uses ab initio calculations to obtain harmonic frequencies and anharmonic constants for the O–H symmetric and asymmetric stretches of H 2SO 4 in its C 2, C s , C 1 a , and C 1 b configurations. In addition, a high-resolution potential energy surface is calculated as a function of both OS–O–H dihedral angles in order to accurately obtain minimum and saddle point energies. The resulting peak positions and Boltzmann populations are compared to experimental frequencies and intensities and provide evidence for the assignment of rotamers in H 2SO 4 as suggested in recent work.