CALCULATIONS OF HIGHLY EXCITED VIBRATIONAL ENERGIES OF HCN(N1, O, N3) - A TEST OF A 2-MODE MODEL, AND COMPARISON WITH EXPERIMENT

Accurate three-mode vibrational calculations of energies of highly excited overtone and combination stretch states of HCN(n1, 0, n3) are presented using the Murrell-Carter-Halonen potential. The calculations employ rotated, mass-scaled Jacobi coordinates, and a bending basis adapted specifically for the ground bend states. The three-mode energies are compared with the results of a simple, two-mode stretch model of Botschwina which includes bend-stretch coupling perturbatively. Comparisons are also made with previous three-mode calculations for lower energy states, as well as with experimental energies.