title: A structural and theoretical investigation of equatorial cis and trans uranyl phosphinimine and uranyl phosphine oxide complexes UO2Cl2(Cy3PNH)2 and UO2Cl2(Cy3PO)2.
abstract: Phosphinimine ligands (Cy3PNH) readily react with UO2Cl2(THF)3 (THF=tetrahydrofuran) to give UO2Cl2(Cy3PNH)2, which contains strong U-N interactions and exists as cis and trans isomers in the solid and solution state. Solution NMR experiments and computational analysis both support the trans form as the major isomer in solution, although the cis isomer becomes more stabilized with an increase in the dielectric constant of the solvent. Mayer bond orders, energy decomposition analysis, and examination of the molecular orbitals and total electron densities support a more covalent bonding interaction in the U-NHPCy3 bond compared with the analogous bond of the related U-OPCy3 compounds.
authors.affiliation: Department of Chemistry, University College London, 20 Gordon Street, London WC1H, UK.
authors.forename: L Jonas L
authors.initials: LJ
authors.lastname: Häller
authors.forename: Nikolas
authors.initials: N
authors.lastname: Kaltsoyannis
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Sarsfield
authors.forename: Iain
authors.initials: I
authors.lastname: May
authors.forename: Stéphanie M
authors.initials: SM
authors.lastname: Cornet
authors.forename: Michael P
authors.initials: MP
authors.lastname: Redmond
authors.forename: Madeleine
authors.initials: M
authors.lastname: Helliwell
mesh_terms: D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry*; D013237:Stereoisomerism; D014501:Uranium / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D010720:Phosphines; D014501:Uranium