Vibronic Energy and Dipole Moment of HD

Abstract

The HD molecule has been treated by perturbation theory using the complete nonrelativistic four‐particle Hamiltonian. In the zeroth order the calculations have been carried out with a 147‐term variational wavefunction. The resulting energies and expectation values of several operators for the ground state and for the first vibrationally excited state are reported. The computed ground‐state dissociation energy, D₀, is by 1.9 cm⁻¹ larger than the experimental value. By treating the mass difference of the nuclei as the perturbation parameter, a 103‐term correction function was computed which yields the second‐order correction to the energy E⁽²⁾=−0.04664 cm⁻¹, and the dipole moment of the molecule μ=1.54 10⁻³ D.