MCSCF study of the spin-orbit coupling in OH (X2Πi)

Abstract

Full-valence MCSCF calculations were performed for the X 2Π i state of OH in that it was hoped that these would predict the spin-orbit coupling A(r) to within a few tenths of a wavenumber over the entire range of r. The functional form was correct but the actual values did not meet our expectations. We briefly considered higher-order relativistic corrections. A universal even-tempered basis set was tested relative to an ‘extended’, optimized basis. The universal basis set did remarkably well and highlighted significant r-dependent and, presumably, state dependent problems with the smaller basis.