Coulomb energy Covalent configurations

Bohr atomic model bonding energy coulombic force covalent bond dipole (electric) electron configuration electronegative... 

The first term corresponds to the Coulomb potential, and the second term corresponds to the repulsive potential (fo is a constant for unit adjustment, a,- is the size, and bj is the stiffness of atom i), which gives a good account of the repulsive interactions arising from the overlap of electronic clouds. The third term in Eq. 16.52 corresponds to the Morse potential which represents covalent interactions, where Dy is the bond energy (determined from the second term of Eq. 16.42), Pij is the form factor, and ro is the bond length at minimum energy. AU these parameters are determined from TB-QC calculations of the same atomic configuration. 

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