Fig. 8: The nature of M-O bonding in M(OAr)4.

a The σ- and π-type M-O bonding NLMOs for Np(OAr)4 at ambient pressure. The NLMOs for the other systems are similar. b The metal contribution (%M), averaged from σ and two π, are shown with relative contributions from d (dark), and f (light) orbitals depicted. There is no significant s- or p-orbital (<2 and <0.1% respectively) contribution. The raw data for this figure are available in Supplementary Table 10).