A semiempirical method of calculating a potential-energy (reaction) surface, based on a simplified quantum-mechanical equation (the London equation).
Source:
PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 171 (https://doi.org/10.1351/pac199668010149)