A THEORETICAL-STUDY OF THE QUANTUM STATES OF HYDROGEN IN NIOBIUM

We present calculations of the energies and wave functions for the vibrational ground state and over 40 excited states of a hydrogen impurity in niobium. Predictions are also given for the transition intensities measured by neutron scattering. The calculations are based on an interaction model for the niobium-hydrogen system developed previously. The aims of the work are to investigate the nature of the quantum states and to show how comparisons of the energies and transition intensities with experiment can be used to test the interaction model. It is shown that for excitation energies above approximately 0.2 eV, many of the states differ greatly from the harmonic oscillator states often assumed in previous analyses. Agreement of the excitation energies and intensities with experimental data is fairly good, though problems of assignment for higher experimental transitions hamper the comparison. It is suggested further that calculations of the present kind will help resolve these problems.