Dynamics of selected rovibronic eigenstates in the V system of carbon disulfide 12,13CS2 Original Research Article

The dynamics of individual eigenstates of carbon disulfide, 12CS2 and 13CS2, resulting from the interaction of rovibronic levels of the 1B2 state with background states, have been investigated in the lowest vibronic state 10V. Using time-resolved spectroscopy with FTL nanosecond laser pulses of jet-cooled molecules, eigenstate absorption intensities, linewidths γ = 1/τ = (0.6–6.0) × 105 s−1 , and magnetic properties were determined, with the latter measured by Landé g factors of up to 0.04 in 12CS2 and hyperfine splittings of up to 10 MHz in 13CS2. The intensities and linewidths were found to be linearly correlated in sets of eigenstates of a rovibronic level. This behaviour revealed the background states to be essentially dark, allowing us to estimate the linewidths of the zero-order states. Hyperfine splittings and g factors show no simple correlation with the intensity, a finding which is attributed to the second-order origin of the background state magnetic properties. Based on the density and the characteristics of the eigenstates, a coupling scheme is proposed, for which the background states represent rovibronic levels of the evsB2 spin component of the 3A2 electronic state interacting with highly excited rovibronic levels of the 1Σ+g electronic ground state.