Abstract

Excitation spectra and the Zeeman spectra of CS2 in the region of 31320-31445 cm-1were measured with sub-Doppler resolution. Observed rotational lines were classified to 14 series of lines (vibronic bands) and were named by the wavenumbers of their band origins. The 31344.9 band is the strongest one and is assigned as the main band of the V1B20v20(K=0)X1g+ 0000 transition. Most of the extra bands may be allowed by the vibronic interaction between the V1B20v20(K=0) level and singlet levels, which are mostly high vibrational levels of the 1A1(X1g+) state. The Zeeman splittings are observed for several lines in almost all bands. These may be originating from the spin-orbit interaction between the rotational levels, which have accidentally nearly the same energy, of the 1A1(X1g+) state and the 3A2 (3Δu ) or/and 3B2 (3Δu) state.