Methane dimer rovibrational states and Raman transition moments.

Benchmark-quality rovibrational data are reported for the methane dimer from variational nuclear motion computations using an ab initio intermolecular potential energy surface reported by [M. P. Metz et al. , Phys. Chem. Chem. Phys. , 2019, 21 , 13504-13525]. A simple polarizability model is used to compute Raman transition moments that may be relevant for future direct observation of the intermolecular dynamics. Non-negligible Δ K ≠ 0 transition moments arise in this symmetric top system due to strong rovibrational couplings.