SPECTROSCOPIC PROPERTIES AND POTENTIAL-ENERGY CURVES OF SOME LOW-LYING ELECTRONIC STATES OF ALO, ALO+, LAO, AND LAO+ - AN AB-INITIO CASSCF STUDY

Results of CASSCF state-averaged calculations on the lowest electronic states of LaO and LaO+ are reported in this work. For comparison, some low-lying electronic states of AlO and AlO+ are also reported. The ground state of LaO was found to be the X(2) Sigma(+) (R(e) = 1.987 Angstrom, omega(e) = 794 cm(-1)) with a low-lying A(2) Delta excited state. Five more excited states below 26000 cm(-1) were found. The first ionization potential (IP) is found at 5.16 eV, resulting in an X(1) Sigma(+) ground state for the LaO+ diatom, in opposition to AlO+ for which and X(3) Pi ground state has been found. Analysis of the wave functions, dipole moments, and Mulliken populations reveal that the bonding is quite ionic in both systems. (C) 1994 John Wiley & Sons, Inc.