Low-lying electronic states of InBi: a configuration interaction study

Multireference singles and doubles configuration interaction (MRDCI) method has been used to study the low-lying electronic states of InBi. The calculations include relativistic effective core potentials (RECP) and spin-orbit operators of In and Bi atoms. Potential energy curves of 46 Lambda-S states, of which 34 states correlate with the lowest three dissociation limits, have been computed. Spectroscopic properties of 22 Lambda-S bound states of InBi within 42,000 cm(-1) of energy are reported. The dissociation energy of the ground state of InBi is estimated to be 114 kJ mol(-1) as compared with the observed value of 153.6 +/- 1.7 kJ mol(-1). The influence of d-correlation on the ground state has been tested. Effects of the spin-orbit coupling on the potential energy curves and spectroscopic parameters are studied. Transition probabilities of electric dipole-allowed transitions such as A(3)Pi-X(3)Sigma(-), A(3)Pi-(3)Pi, 2(1)Sigma(+)-1Pi, 2(1)Sigma(+)-(1)Sigma(+) are calculated. The radiative lifetimes of A(3)Pi and 2(1)Sigma(+) at v' = 0 are found to be 1.0 and 7.2 mus, respectively. The A0(+) state is identified as an important state which survives from the predissociation. Three transitions such as A0(+)-X(1)0(+), A0(+)-X(2)1, and A0(+)-(3)Pi(0)(+) are studied. The MRDCI estimated spectroscopic properties of InX (X similar or equal to P, As, Sb, l3i) molecules are compared. (C) 2003 Elsevier Science B.V. All rights reserved.