The Lyman and Werner Bands of Deuterium

Abstract

The Lyman and Werner bands of D2 have been measured under high resolution and their analysis has been extended. From this analysis the rotational and vibrational levels of the ground state of D2 have been evaluated up to the last vibrational level ν = 21 which lies only 2 cm−1 below the dissociation limit. The deviations of the observed ΔG(ν + 1/2) and Bv values from theoretical values given by Kolos and Wolniewicz on the basis of ab initio calculations are very small but systematic and are probably due to the neglect of nonadiabatic corrections in the theoretical calculations. Similar comparisons have been made for the lower vibrational levels of the B1Σu+ and C1Πu− states. Here the differences between theory and experiment are somewhat larger. The observed electronic excitation energies agree with the theoretical ones within 15 cm−1 for 1Σu+ and 8 cm−1 for 1Πu−.