Approaching Phosphorescence Lifetimes in Solution: The Two-Component Polarizable-Embedding Approximate Coupled-Cluster Method.

Theoretical description of phosphorescence lifetimes in the condensed phase requires a method that takes into account both spin-orbit coupling and solvent-solute interactions. To obtain such a method, we have coupled our recently developed two-component coupled-cluster method with singles and approximated doubles to a polarizable environment. With this new method, we investigate how different solvents effect the electronic phosphorescence energies and lifetimes of 4H-pyran-4-thione.