Comparer des méthodes

	Interaction de Configurations	EXAFS
Domaine	Spectroscopie	Spectroscopie
Famille	Process / pipeline	Process / pipeline
Année d'origine	1960	1971
Auteur d'origine	Clemens Roothaan	Edward Stern
Type	Computational method	Synchrotron technique
Source fondatrice	Roothaan, C. C. J. (1960). New developments in molecular orbital theory. Reviews of Modern Physics, 32(2), 179-185.	Sayers, D. E., Stern, E. A., & Lytle, F. W. (1971). New technique for investigating noncrystalline structures: Fourier analysis of the extended X-ray absorption fine structure. Physical Review Letters, 27(18), 1204-1207.
Alias	CI, configuration interaction method, CI calculations	EXAFS spectroscopy, X-ray absorption spectroscopy
Apparentées	3	3
Résumé	Configuration Interaction (CI) is a post-Hartree-Fock quantum chemistry method that improves upon mean-field molecular orbital theory by treating electron correlation through a linear combination of electronic configurations. Introduced by Roothaan in 1960, CI corrects for the fundamental limitation of single-determinant theory by allowing the wavefunction to be a superposition of excited-state Slater determinants, systematically accounting for electron-electron interactions.	Extended X-ray Absorption Fine Structure (EXAFS) is a synchrotron-based X-ray spectroscopy technique that measures the local geometric and electronic structure around a specific atom in any material, crystal or amorphous. Discovered by Sayers, Stern, and Lytle in 1971, EXAFS reveals interatomic distances, coordination numbers, and disorder in the atomic environment by analyzing oscillations in the X-ray absorption spectrum above an absorption edge.