MICROWAVE SPECTRUM OF CLO RADICAL

Rotational transitions in the 2Π 3 2 and 2Π 1 2 electronic states have been investigated for both the 35ClO and 37ClO radicals by means of Stark modulated microwave spectrometers. Improved values were obtained for the rotational constants, Λ-doubling parameters and hyperfine constants of both radicals. It was found necessary to consider the effect of centrifugal distortion including the dependence of the spin-orbit coupling constant A on the internuclear distance. The distortion constant De was 0.077 ± 0.016 MHz and the value of A′ = (r dA dr) at the equilibrium internuclear distance was 320 ± 60 cm-1, assuming a value for A determined from electron-paramagnetic-resonance data. The equilibrium internuclear distance re was calculated to be 1.569 ± 0.001 Å from the rotational constants B0 for 35ClO and 37ClO. A detailed analysis of the second order Stark effect of the F = 0 ← 1 and F = 1 ← 1 components of the upper series of the J = 3 2 ← 1 2 rotational transition in the 2Π 1 2 state of 35ClO was performed and the electric dipole moment was determined to be 1.239 ± 0.010 D. This value was confirmed for the 2Π 3 2 state of 35ClO where the Stark effect is first-order for weak electric fields. (The indicated undertainties represent three times the standard errors of the reported values). © 1969.