 Electron localization function

The Electron Localization Function (ELF) is a theoretical tool used in quantum chemistry and solid-state physics to analyze the spatial distribution of electrons in a many-body system, particularly in molecular and solid-state systems. It provides insights into the localization of electrons in a chemical system, which in turn helps in understanding bonding, electronic structure, and reactivity. The ELF is defined mathematically in terms of the electron density and the kinetic energy density.