A spectroscopic study of HCP, the phosphorus analogue of hydrocyanic acid

Abstract

The ultraviolet absorption spectrum of HCP has been observed from 4100 Å to about 2350 Å, and seven electronic transitions have been identified. Three of these transitions involve excited singlet states and four of them involve excited triplet states. The symmetries, energies, and equilibrium conformations of these states are listed below:[Formula: see text]Some observations have also been made on the vibration–rotation energy levels of the ground electronic state, [Formula: see text], of HCP. The fundamental vibration frequencies (in cm −1 ) are ν 1 = 3216.9, ν 2 = 674.7, and ν 3 = 1278.4.