Structures, spectroscopic and thermodynamic properties of U₂On (n = 0 ∼ 2, 4) molecules: a density functional theory study.

The equilibrium structures, spectroscopic and thermodynamic parameters [entropy (S), internal energy (E), heat capacity (C p)] of U₂, U₂O, U₂O₂ and U₂O₄ uranium oxide molecules were investigated systematically using density functional theory (DFT). Our computations indicated that the ground electronic state of U₂ is the septet state and the equilibrium bond length is 2.194 Å; the ground electronic state of U₂O and U₂O₂ were found to be X³Φ and X³Σ(g) with stable C(∞v) and D(∞h) linear structures, respectively.