A computational study of the reaction mechanism for the solid state photolysis of cis-2,6-di(1-cyclohexenyl)cyclohexanone (1) was carried out using density functional theory. Compound 1 was designed to explore the competition between several possible pathways, but mainly to discern from alpha-cleavage/decarbonylation (Norrish type I), and gamma-hydrogen abstraction followed by cyclization (Norrish type II-Yang). The triplet state reaction coordinates for the type I and II photochemistry were obtained computationally. While calculations predict that the type I reaction should be predominant in the triplet state due to lower barrier heights for the process, the observed reactivity in the solid state favored the type H process. By correlating the results from calculations and experiments with singlet/triplet sensitizers/quenchers, it was found that the observed reactivity takes place along the singlet manifold.