12069-98-6Relevant 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.
