Ab Initio Variational Calculations of Molecular Vibrational-Rotational Spectra

This monograph deals with ab initio variational calculations of vibrational-rotational spectra of bent triatomic molecules. It gives a comprehensive derivation of the Eckart-Watson Hamiltonian in terms of an "f" co-ordinate system. The derived Hamiltonian is in the most general form and so is shown to collapse to C2v and D3h rectilinear Hamiltonians. Concommitant with the derived Hamiltonians, a complete solution algorithm of the nuclear Schrodinger equation is detailed. The eigenfunctions of numerical finite-element solutions of three one-dimensional Schrodinger equations are spliced together to form configurational trial basis functions for the variational solution of the three-dimensional vibrational problem. These solutions, together with the symmetric top eigenfunctions, span the full vibrational-rotational Hamiltonian. Examples of variational solutions of the full vibrational-rotational Hamiltonians are given throughout the text.