An ab initio study of the hyperfine structure in the X ² Π electronic state of HCCS-calculation of vibronically averaged components of the anizotropic hyperfine tensor

Abstract

Theresults of ab initio calculations of the vibronically averaged components of the anisotropic magnetic hyperfine tensor in the low-lying vibronic species of the X 2 Π electronic state of the HCCS radical are reported. The electronically averaged hyperfine coupling constants for hydrogen, deuterium, 13 C and 33 S are obtained as functions of two bending vibrational modes by the density functional theory method. The vibronic wave functions are calculated with the help of a variational approach which takes into account the Renner-Teller effect and spin-orbit coupling. The results of ab initio calculations are compared to the corresponding experimental findings. © 2005 Taylor & Francis Group Ltd.