MICROWAVE SPECTROSCOPY OF THE UPSILON=3-10 LEVELS OF CN(X2-SIGMA+)

The fine-structure and hyperfine-coupling constants for the (CN)-C-12(X 2-SIGMA+), upsilon = 3-10 levels were determined by an analysis of the microwave spectrum. The second-order perturbation treatment for the spin-rotation interaction constants, gamma-upsilon, is found to be sufficient for the (CN)-C-12(X 2-SIGMA+), upsilon = 5-10 levels. The transition frequencies for the upsilon = 4-10 levels are analyzed by including the X 2-SIGMA+ approximately A 2-PI(i) local perturbations in the fine-structure Hamiltonian matrix. The gamma-upsilon constants thus obtained fit the second-order expression. The electronic terms of the X 2-SIGMA+ approximately A 2-PI(i) spin-orbit and rotational-electronic interactions are determined as functions of the internuclear distance.