Rotational Analysis of Bands of the Transition of PH2

Abstract

Rotational analyses have been carried out for the 0ν′20–000 bands of the [Formula: see text] electronic transition of PH2 with ν′2 = 1–8. Approximately 1000 lines have been assigned. The earlier analysis of the 000–000 band has been extended and improved molecular constants obtained. The Hamiltonian used for this band does not fit the excited state levels with [Formula: see text]. Term values are therefore given for all observed levels. Empirical formulas are presented which give approximate fits to the higher levels. Numerous rotational perturbations are found in the excited state. Perturbations up to 0.6 cm−1 are also found in the 000 level of the excited state. These latter perturbations can only be caused by the higher vibrational levels of the ground state.