Theoretical studies of organometallic complexes of uranium involving nitrogen ligands using density functional approaches.

Density functional calculations are used to investigate the structure and bonding in several unusual cyclopentadienyl complexes of uranium with nitrogen-containing ligands. The U(VI) imido complex Cp2U(NPh)2 and the U(IV) amido complex Cp2(NHPh)2 are examined and the important orbitals involved in the U-N bonds are analyzed. The recently synthesized 22-electron U(IV) hydrazonato complex U(IV) Cp*2U(Me-N-N=CR2)2 is explored from the standpoint of an expanded valence shell, and the differences between the structures and thermochemistries of U(IV) and Zr(IV) complexes are probed.