 Energy-loss near-edge structure

Energy-loss near-edge structure is the detailed shape near an inner-shell excitation edge in an electron energy loss spectroscopy measurement. Transition probabilities sample accessible unoccupied electronic states, so local bonding and orientation affect the edge shape as well as elemental identity.

Comparing two specimens containing the same element can therefore reveal different electronic environments. Interpretation must account for instrumental energy resolution, the incident beam's energy spread and lifetime broadening of the states involved. ^[ref] A small peak difference alone does not uniquely determine one atomic arrangement.