Theoretical study on the molecular and crystal structures of nitrogen trifluoride and its adduct with BF3

The molecular and crystal structure of the adduct NF3⋅BF3 was studied computationally using density functional theory. It shows that the adduct exists in the form of a complex but is not ionic. The heats of formation in the gas and the condensed phase of the adduct are −1266.09 and −1276.37 kJ ⋅mol−1, respectively, which indicates that it is stable under atmospheric conditions. The crystal form belongs to P21/c space group. The calculated large band gap (ΔEg) of the crystal proves that it is stable. The conduction band (LUCO) is mainly contributed by the p orbital of N atom and the valence band (HOCO) from the p orbital of F atom.