Calculations of spectral-line parameters in the microwave region

Abstract

Computations of width and shift parameters of rotational spectral lines in the microwave region have been performed using the Frost extension (1976) of the Anderson-Tsao-Curnutte theory (1962), a modification of this theory, the theory of Murphy and Boggs (1967) and the Cattani modification (1972) of the Murphy and Boggs theory. The parameters calculated are for the lines OCS J=2 to 3; CH3Cl J,K=0,0 to 1,0; CH3I J,K=1,0 to 2,0 (8a foregin to foreign and CH3CN J,K=5,2 to 6,2 both self-perturbed and perturbed by selected foreign gases. The results are compared with experimental data. The two modified theories agree closely with one another and offer better overall agreement with the experimental widths and shifts. Differences between the calculations and the experimental results are a measure of the inadequacies of theories of this type in the region of intermediate collision impact parameter.