The Chemical Bond in Several Di-Atomics - Orbital Exchange Calculations

This paper extends orbital exchange method calculations to include a series of di-atomic molecules: NO+,CO, CO+, BO, BF, BeF, LiF, and Li2. BF, BeF and LiF are more accurately described as B+F-, Be+F- and Li+F- as there is no net overlap of the orbitals on the bonding ions. The sigma orbitals on B+ and Be+ are made orthogonal to the F- sigma orbitals and the sigma orbitals on F- made orthogonal to the 1s core orbitals of B+ ,Be+, and Li+. NO+, CO, CO+ and BO have dual sigma bonds and exhibit pi resonance. The bond length results for NO+, CO, and CO+ are within about 0.005 Angstrom units of experiment. The bond energy results for NO+, CO, and CO+ are within 2 percent of experiment Precise bond lengths are not consistently obtained for the “ionic” di-atomics, B+F-, Be+F- and Li+F, primarily because these are not subject to the usual overlap≤1.0 constraint. Precise bond energy and bond length are not obtained for Li2 (and to a lesser extent BO) because of the difficulty in precisely defining the orthogonalization parameters for the light elements.