D3d distortion in CsUF6

A slight D_3d distortion on the octahedral UF₆^? complex splits the Γ^'₈ and Γ₈ octahedral levels into four doublets. These doublets and other electronic levels of the CsUF₆ ground configuration have been identified according to their vibronic side-bands. In the calculation of the crystal field Hamiltonian, the amount of D_3d distortion on the UF₆^? octahedron is treated as the parameter, Δ. The interactions of the 5f electron of the UF₆^? complex contains five parameters: ξ_5f, B₂⁰, B₄⁰, B₆⁰ and Δ. The calculated energy spectrum and the g-tensor of the ground state show good agreement with the experimental measurements.