Theoretical electronic structure of the molecule ScI

Abstract

Abstract Theoretical investigation of the 18 lowest electronic states of the molecule ScI in the representation 2 S +1 Λ (±) has been performed via CASSCF and MRCI (single and double excitation with Davidson correction) calculations. To the best of our knowledge these calculated electronic states are the first ones from ab initio methods. Thirteen electronic states between 4,500 cm −1 and 21,000 cm −1 have been studied for the first time and have not yet been observed experimentally. The harmonic frequency ω e , the internuclear distance R e , the electronic transition energy with respect to the ground state T e , and the rotational constant B e have been calculated for the considered electronic states. By using the canonical functions approach the eigenvalues E υ and the rotational constants B υ have also been calculated for the six lowest‐lying electronic states. The comparison of these results with the theoretical and the experimental data available in the literature shows a good agreement. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009