An HMO »Extended« Free Valence Index and its Application
Hugo O. Villar, Alberto Luis Capparelli, Alejandro Spina · University of Zagreb University Computing Centre (SRCE) · 1986
An extended free valence index defined in the HMO framework and its modification is presented .. It has been applied to several molecules containing heteroatoms and non-benzenoid systems, where the classical free valence index fails in predicting the reactivity positions.This index gives, by direct inspection, the most probable positions for electrophilic (ES) and nucleophilic (NS) substitutions.