Non-empirical valence-shell self-consistent field molecular-orbital calculations on Group 5 tri- and penta-halides

Abstract

Non-empirical valence-shell SCFMO calculations have been made on the tri- and penta-fluorides and chlorides of the elements N, P, As, and Sb. The calculations use a minimal basis plus d orbitals for the Group 5 atom. The calculated geometries of the trihalides agree well with experimental data. The dissociation energy for the process MX₅→ MX₃+ 2X has been calculated and is negative for NF₅, NCl₅, and AsCl₅. Calculations on the mixed phosphorus pentahalides with trigonal-bipyramid structures show that fluorine is energetically preferred in the equatorial positions in all cases.