Oscillator Strengths for IR Rovibrational Transitions of CO

Abstract

We have solved the nuclear Schrödinger radial equation to derive wavefunctions and rovibrational energy levels of the carbon monoxide molecule 12C 16O in its ground electronic state X 1Σ + at a spectroscopic accuracy. We then calculated the dipole matrix elements for transitions involving vibrational quantum numbers up to v = 15 and rotational quantum numbers up to J = 200. Calculations were carried out for the fundamental (Δ v = 1) and the three first overtone (Δ v = 2, 3, 4) bands. For the transition matrix elements there is typically a 10% difference from previous results due to recent values of the dipole moment function. This gives a significant 20% difference for the absorption oscillator strengths which are computed for this set of 21 600 lines.