The effect of density functional and dispersion interaction on structure and bonding analysis of uranium(VI) nitride complex [Ntriple bond; length of mdashU{N(CH2CH2NSiMe3)3}]: A theoretical study

Geometry and bonding energy analysis of uranium(VI) nitride complex [Ntriple bond; length of mdashU{N(CH2CH2NSiMe3)3}] were investigated with the DFT, DFT-D3 and DFT-D3(BJ) methods using density functionals (BLYP, BP86, PW91, PBE, revPBE and TPSS). The BLYP functional yields a Utriple bond; length of mdashN bond distance of 1.788 Å for the model complex [Ntriple bond; length of mdashU{N(CH2CH2NSiMe3)3}] which is in close agreement with the experimental value of the Utriple bond; length of mdashN bond distance of 1.799(7) Å for [Ntriple bond; length of mdashU{N(CH2CH2NSiiPr3)3}]. The calculated Mayer bond order (2.95) and Gopinathan–Jug bond order (3.18) indicate that the Usingle bondN bond in this complex is essentially Utriple bond; length of mdashN triple bonds. The electrostatic interaction is significantly smaller than the covalent bonding. The bond dissociation energy (BDE) is largest for the functional PBE and smallest for the functional TPSS. The DFT-D3 dispersion corrections are 5.3 kcal/mol (BLYP) and 5.0 kcal/mol (TPSS).