SPIN UNCOUPLING IN 3A2 CS2 STUDIED BY HIGH-RESOLUTION ZEEMAN AND HYPERFINE QUANTUM BEAT SPECTROSCOPY

The magnetic properties of the (evs)B2 spin component of the 3A2 state in the molecule CS2 have been investigated with a resolution of approximately 100 kHz by quantum beat spectroscopy, in a supersonic jet. Zeeman-level tuning in (CS2)-C-12 and (CS2)-C-13, providing Lande g factors, and measurements of the (CS2)-C-13 nuclear hyperfine structure were carried out, particularly to investigate their J dependence. Based on these results, it is proposed that both the magnetic moment and the hyperfine splitting are dominated by spin-uncoupling interactions, described in the rotational Hamiltonian by B(J-S).2 In addition, the g factors and rotational state lifetimes were used to provide spectroscopic assignments and to elucidate details of the state mixing.