The BEBOP model attempts to extrapolate the total system atomization energies and bond energies using SQM-like formulas that employ reliable HF orbital populations. The current model includes hybridization and short-range repulsion to describe the energy of systems containing H, Li, Be, B, C, N, O and F. To generate the necessary population data, including P 12 , ROHF/6-311+G(3d2f,2df,2p) calculations were used with the MinPop algorithm, which projects an extended basis set onto a minimum basis set, providing a reliable Mulliken population analysis for bond orders and hybridization. However, the charges obtained are not always realistic. Since we observed that the charge transfer energy was generally balanced by the resulting electrostatic interaction energy, both terms were neglected. The parameters were determined by fitting restricted-open-shell (RO) model chemistry based on the complete basis set (CBS)-quadratic Becke3 (QB3), or ROCBS-QB3