12037-15-9Relevant articles and documents
Infrared spectra and quantum chemical calculations of the uranium carbide molecules UC and CUC with triple bonds
Wang, Xuefeng,Andrews, Lester,Malmqvist, Per-Ake,Roos, Bjoern O.,Goncalves, Antonio P.,Pereira, Claudia C. L.,Marcalo, Joaquim,Godart, Claude,Villeroy, Benjamin
, p. 8484 - 8488 (2010/08/05)
Laser evaporation of carbon-rich uranium/carbon alloys followed by atom reactions in a solid argon matrix and trapping at 8 K gives weak infrared absorptions for CUO at 852 and 804 cm-1. A new band at 827 cm -1 becomes a doublet with mixed carbon 12 and 13 isotopes and exhibits the 1.0381 isotopic frequency ratio, which is appropriate for the UC diatomic molecule, and another new band at 891 cm-1 gives a three-band mixed isotopic spectrum with the 1.0366 isotopic frequency ratio, which is characteristic of the linear CUC molecule. CASPT2 calculations with dynamical correlation find the C≡U≡C ground state as linear 3∑u+ with 1.840 A bond length and molecular orbital occupancies for an effective bond order of 2.83. Similar calculations with spin-orbit coupling show that the U≡C diatomic molecule has a quintet (λ = 5, δ = 3) ground state, a similar 1.855 A bond length, and a fully developed triple bond of 2.82 effective bond order.
Noble gas - Actinide complexes of the CUO molecule with multiple Ar, Kr, and Xe atoms in noble-gas matrices
Andrews, Lester,Liang, Binyong,Li, Jun,Bursten, Bruce E.
, p. 3126 - 3139 (2007/10/03)
Laser-ablated U atoms react with CO in excess argon to produce CUO, which is trapped in a triplet state in solid argon at 7 K, based on agreement between observed and relativistic density functional theory (DFT) calculated isotopic frequencies 12C16C, 13C16O, 12C18O). This observation contrasts a recent neon matrix investigation, which trapped CUO in a linear singlet state calculated to be about 1 kcal/mol lower in energy. Experiments with krypton and xenon give results analogous to those with argon. Similar work with dilute Kr and Xe in argon finds small frequency shifts in new four-band progressions for CUO in the same triplet states trapped in solid argon and provides evidence for four distinct CUO(Ar)4-n(Ng)n (Ng = Kr, Xe, n = 1, 2, 3, 4) complexes for each Ng. DFT calculations show that successively higher Ng complexes are responsible for the observed frequency progressions. This work provides the first evidence for noble gas - actinide complexes, and the first example of neutral complexes with four noble gas atoms bonded to one metal center.
Quenching of excited uranyl ion during its photochemical reduction by triphenylphosphine: Part III
Sidhu, M S,Chahat, Paramjit,Singh, R J
, p. 517 - 520 (2007/10/02)
Relative rates of bimolecular quenching of excited uranyl ion by some mono and disubstituted benzene derivatives have been measured during its photochemical reduction with triphenylphosphine.For the related compounds in a series it has been found that substitutent groups enriching the aromatic ?-electron could due to resonance stabilization, show an enhanced photophysical quenching action.The substituents decreasing the ?-electron could and delocalization of positive charge over the benzene ring decrease the quenching action.
