Methoden vergleichen

	Konfigurationswechselwirkung	DMRG	XANES
Fachgebiet	Spektroskopie	Spektroskopie	Spektroskopie
Familie	Process / pipeline	Process / pipeline	Process / pipeline
Entstehungsjahr	1960	1992	1975
Urheber	Clemens Roothaan	Steven White	Peter Lee
Typ	Computational method	Computational method	Synchrotron technique
Wegweisende Quelle	Roothaan, C. C. J. (1960). New developments in molecular orbital theory. Reviews of Modern Physics, 32(2), 179-185.	White, S. R. (1992). Density matrix formulation for quantum renormalization groups. Physical Review Letters, 69(19), 2863-2866.	Lee, P. A., & Pendry, J. B. (1975). Theory of extended x-ray absorption fine structure. Physical Review B, 11(8), 2795-2811.
Aliasnamen	CI, configuration interaction method, CI calculations	DMRG, density matrix renormalization, tensor network	XANES spectroscopy, near-edge X-ray absorption
Verwandt	3	3	3
Zusammenfassung	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.	Density Matrix Renormalization Group (DMRG) is a powerful computational method for solving strongly correlated quantum systems, particularly one-dimensional lattice models and quantum chemistry problems. Introduced by White in 1992, DMRG uses a variational approach and tensor-network representation to efficiently describe quantum ground states and excitations, achieving numerical accuracy competitive with exact diagonalization for systems that other methods cannot treat.	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.