We present a detailed theoretical investigation of the structure and d
ynamics of the S-3 excited state of CS2. The excited state is treated
using equation-of-motion coupled-cluster (EOM-CC) theory, and analytic
gradients are used in determining the vibrational frequencies. Inform
ation from the structure calculations is used to construct a model pot
ential surface. Time-dependent wave packet methods are used to generat
e the transition state spectrum corresponding to collinear CS2. The sp
ectrum is comprised of transition state resonances which are assigned
via a spectral quantization method. The energies and lifetimes of the
spectral features are related to recent experimental measurements. (C)
1997 American Institute of Physics. [S0021-9606(97)02641-X].