A theoretical probe for pentavalent bis-imido uranium complexes containing diverse axial substituents and equatorial donors: UN multiple bond and structural/electronic properties

Relativistic DFT unraveled that the changes of the R substituents as well as the number and the position of equatorial donors are capable of tuning structural and electronic properties of bis-imido uranium complexes. Their U(V) 5f1 configuration can mainly reflected by the HOMO with over 96% metal character. A weak UVN triple bond is proposed; the weakest one is found for 3Ph and elucidated by two π(UN) backbonding orbitals.