Theoretical study of the electronic states of AlO and AlO-

The spectroscopic constants of the excited doublet and quartet states of al uminium oxide have been calculated from potential energy functions obtained by the ab initio MRCI approach. Such constants are given also for several states that have not yet been observed. The characteristics of the calculat ed electric dipole and transition moment functions are discussed in connect ion with the ionicity and avoided crossing regions of the excited states. T he spin-orbit interactions between electronic states have been calculated f or those cases where this type of coupling was assumed to be responsible fo r pertubations of the spectra. Also for the bound electronic ground state o f the AlO- anion the spectroscopic constants are given and its photoelectro n spectrum is discussed. (C) 1999 Elsevier Science B.V. All rights reserved .