Theoretical study of molecular dipole moment functions. I. The X 1Σ+ state of CO

Abstract

Approximate dipole moment functions for the X ¹Σ⁺ state of CO have been calculated using several configuration interaction wavefunctions. The best theoretical results obtained for the dipole derivatives at R_e and vibrational transition matrix elements are found to be in quantitative agreement with available experimental data. The theoretical dipole moment functions, in contrast to empirical functions, possess correct long range behavior. Through a detailed comparison of different approximate wavefunctions, useful information has been obtained on the relative importance of different types of correlation effects on the accurate determination of molecular dipole moment functions.