Two-phonon Raman rates can only be reliably obtained by considering the (pseudo-)acoustic phonons in the solid-state, so this calculation cannot be performed using the gas-phase vibrational spectrum. We therefore also calculated the spin-phonon coupling and magnetic relaxation rates using the solid-state phonon modes and supercell expansions commensurate with the q-point grids on which the ab initio frequencies and linewidths were obtained.