Electronic Structure and Spectroscopic Studies of the Molecule ScS

Abstract

Theoretical investigation of the lowest electronic states of ScS molecule, in the representation 2s+1 Λ (+/-) , has been performed via CASSCF and MRCI (single and double excitations without Davidson correction) calculations. The calculated potential energy curves (PECs), permanent dipole moment curves (PDMCs), and spectroscopic constants are reported for the 10 lowest electronic states. The eigenvalues E v , the rotational constants B v , and the centrifugal distortion constants D v have been calculated for various vibrational levels. The comparison of the present results with the available experimental data in literature shows an overall good agreement. To the best of our knowledge, 6 electronic states of the ScS molecule, between 11600 cm -1 and 15000 cm -1 are not yet observed experimentally and are investigated in the present work for the first time.