Estimates of energies of core exchange

Energies of core exchange, δ, for some first row elements have been estimated from thermodynamic data and experimental core electron binding energies. Values of energies of core exchange extend the equivalent cores method to allow the calculation of absolute binding energies as well as shifts. In some cases it is possible to estimate the differences in binding energy without requiring heats of formation of gaseous cations. The values of δ obtained from LCAO-MO-SCF calculations show similar trends although the absolute values may differ by a few electron volts.