title: Reactions of uranium atoms with ammonia: infrared spectra and quasi-relativistic calculations of the U:NH3, H2N--UH, and HN==UH2 complexes.
abstract: Ammonia molecules interact with U atoms, and the resulting U:NH3 complex rearranges upon visible irradiation to form the H2N--UH and HN==UH2 molecules in excess argon. These products are identified by functional group frequencies, 15NH3 and ND3 isotopic shifts, and comparison to frequencies calculated by using density functional theory. The N==U pi bond in HN==UH2 is enhanced by partial triple-bond character through N(2p) to U(5f) conjugation, which is comparable to that found in the analogous HN==ThH2 molecule. These products also form complexes with additional ammonia molecules in the matrix. The interesting higher-energy N[triple chemical bond]UH3 complex is not formed.
authors.affiliation: Department of Chemistry, University of Virginia, P.O. Box 400319, Charlottesville, VA 22904-4319, USA.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Wang
authors.forename: Lester
authors.initials: L
authors.lastname: Andrews
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Marsden