手法を比較

	Configuration Interaction	XANES
分野	分光学	分光学
系統	Process / pipeline	Process / pipeline
提唱年	1960	1975
提唱者	Clemens Roothaan	Peter Lee
種類	Computational method	Synchrotron technique
原典	Roothaan, C. C. J. (1960). New developments in molecular orbital theory. Reviews of Modern Physics, 32(2), 179-185.	Lee, P. A., & Pendry, J. B. (1975). Theory of extended x-ray absorption fine structure. Physical Review B, 11(8), 2795-2811.
別名	CI, configuration interaction method, CI calculations	XANES spectroscopy, near-edge X-ray absorption
関連	3	3
概要	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.	X-ray Absorption Near Edge Structure (XANES) is a synchrotron X-ray spectroscopy technique that measures the electronic and geometric structure around a specific atom by analyzing the X-ray absorption spectrum within about 50 eV of an absorption edge. Developed by Lee and Pendry in 1975, XANES is complementary to EXAFS and reveals valence state, local symmetry, and unoccupied orbital structure through near-threshold features and resonances.