CALCULATION OF THE WEAKLY COUPLED 1 AND 2 (1)PI TWIN STATES OF KRB

Spectroscopic properties of all excited states of KRb dissociating into 4s(K)+5s(Rb), 4s(K)+5p(Rb), and 4p(K)+5s(Rb) are studied, using quantum chemical calculations. Only the 1 and 2 Π1 states showed a weak coupling between the 4s(K)+5p(Rb) and the 4p(K)+5s(Rb) components. The dipole moments, atomic orbital populations, and transition dipole moments of those two states showed a twin nature. Calculated Einstein coefficients for the 1 X1 and 2 X1 dipole transitions predict unusually rich band spectra. The intensity distributions of those two transitions showed a remarkable difference. © 1995 The American Physical Society.