Submillimeter-wave spectrum and spectroscopic constants of AsH3 in the (0100) and (0001) vibrational states and joint analysis of submillimeter and infrared data

Abstract The submillimeter-wave spectra of the arsine molecule in the excited vibrational states (0100) and (0001) have been investigated for both allowed R branches ( J + 1 ← J , K ← K ) and weak-intensity “forbidden” Q branches ( K = 3 ← 1, 3 ← 0, 2 ← 0). Weak “forbidden” transitions of the AsH 3 molecule in the (0001) state can be observed due to the increase of sensitivity of a RAD-spectrometer by using quasi-optical cavity absorption cells. As a results of joint analysis of new submillimeter recordings together with the known infrared, microwave, and radiofrequency data, the set of spectroscopic parameters obtained allows one to describe all the available spectroscopic data for the (0100) and (0001) vibrational states of the AsH 3 molecule within experimental uncertainties.