A Relativistic Density Functional Study of the U<sub>2</sub>F<sub>6</sub> Molecule
- 1 School of Science, Xi'an University of Posts and Telecommunications, Xi'an, China
Abstract
All-electronic relativistic density functional theory (DFT) method has been used to study the U 2 F 6 molecule. Results from calculations predict the existence of U 2 F 6 molecule, which has been found to be stable with a multiply bonded U 2 unit. The calculations also predict that D 3d symmetry of U 2 F 6 is more stable than D 3h . The optimized geometries, vibrational frequencies and infrared intensities are reported for D 3d symmetry of U 2 F 6 from Becke Three-parameter Lee-Yang-Parr (B3LYP) function with triple zeta valence plus polarization functions basis set (TZP). The bond dissociation energy (BDE) for U-U bond in the U 2 F 6 was obtained using the same method. In addition, the entropies of U 2 F 6 have been investigated at temperature rang from 0 to 3000K in 10 steps using the B3LYP method.
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