CORIOLIS COUPLING-CONSTANTS AND INERTIAL DEFECT OF B2F4 BY AB-INITIO CALCULATIONS AND THE ITERATIVE METHOD

Structural parameters, harmonic frequencies, and force constants of B2 F4 were obtained in internal coordinates from ab initio RHF calculatio ns with the 6-311G basis set. The results obtained are used to calcul ate the Coriolis coupling constants and the inertial defect for (B2F4) -B-10 and (B2F4)-B-11 and to compare these values with those obtained by using the autoconsistency method. Both the ab initio and the iterat ive force fields, despite some significant differences, reproduce the vibrational wave numbers equally well and yield nearly the same Coriol is coupling constants and inertial defects. The calculated inertial de fects for (B2F4)-B-10 and (B2F4)-B-11 are -0.942 and -0.919 amu Angstr om(2), respectively.