In solid-state physics, the k·p perturbation theory is an approximated semi-empirical approach for calculating the band structure (particularly effective...
12 KB (1,975 words) - 11:29, 25 March 2024
Møller–Plesset perturbation theory (MP) is one of several quantum chemistry post-Hartree–Fock ab initio methods in the field of computational chemistry...
23 KB (2,870 words) - 20:17, 25 November 2023
Frontier molecular orbital theory Ligand field theory (MO theory for transition metal complexes) Møller–Plesset perturbation theory Quantum chemistry computer...
22 KB (2,943 words) - 17:32, 23 June 2024
Electronic band structure (redirect from Band theory)
of a region of free space that has been divided into a lattice. k·p perturbation theory is a technique that allows a band structure to be approximately...
36 KB (4,771 words) - 12:33, 19 July 2024
Schrieffer and P.A. Wolff., Joaquin Mazdak Luttinger and Walter Kohn used this method in an earlier work about non-periodic k·p perturbation theory. Using the...
12 KB (2,124 words) - 12:20, 10 June 2024
E k 1 n E k 2 k 3 2 E k 2 k 4 − V k 2 k 3 V k 3 k 4 V k 4 n V k 1 k 2 E k 1 n E k 2 n E n k 3 E n k 4 + V k 1 k 2 E k 1 n ( | V k 2 k 3 | 2 V k 2 k 2...
70 KB (15,963 words) - 03:05, 20 July 2024
Hartree–Fock method (redirect from Hartree-Fock theory)
function. One of these approaches, Møller–Plesset perturbation theory, treats correlation as a perturbation of the Fock operator. Others expand the true multi-electron...
31 KB (4,729 words) - 12:30, 5 August 2024
density contributes a term in the gradient of the density. In a perturbation theory approach the direct correlation function is given by the sum of the...
79 KB (10,545 words) - 03:52, 13 August 2024
In mathematics, variational perturbation theory (VPT) is a mathematical method to convert divergent power series in a small expansion parameter, say s...
4 KB (428 words) - 13:36, 16 December 2020
cosmological perturbation theory is the theory by which the evolution of structure is understood in the Big Bang model. Cosmological perturbation theory may be...
15 KB (2,050 words) - 13:23, 28 October 2023
electron-hole pairs) and the Sternheimer equation (density-functional perturbation theory). Hohenberg, P.; Kohn, W. (1964). "Inhomogeneous Electron Gas". Physical...
16 KB (2,495 words) - 21:24, 30 October 2023
the theory of semiconductors that are now used in consumer and other electronics. He was one of the main developers of the k·p perturbation theory which...
10 KB (1,175 words) - 17:02, 15 August 2024
In chemistry, valence bond (VB) theory is one of the two basic theories, along with molecular orbital (MO) theory, that were developed to use the methods...
12 KB (1,576 words) - 07:10, 29 April 2024
The Luttinger–Kohn model is a flavor of the k·p perturbation theory used for calculating the structure of multiple, degenerate electronic bands in bulk...
10 KB (2,474 words) - 09:05, 14 February 2024
degenerate perturbation theory, respectively, can be applied in these two cases to solve for the Fourier coefficients C k {\displaystyle C_{\mathbf {k} }} of...
9 KB (1,346 words) - 21:35, 11 March 2024
In mathematics, an eigenvalue perturbation problem is that of finding the eigenvectors and eigenvalues of a system A x = λ x {\displaystyle Ax=\lambda...
27 KB (6,234 words) - 06:43, 8 February 2024
represented by a Feynman diagram according to perturbation theory in quantum mechanics. Quantum field theory emerged from the work of generations of theoretical...
106 KB (14,897 words) - 08:50, 30 July 2024
In mathematics and electronics, cavity perturbation theory describes methods for derivation of perturbation formulae for performance changes of a cavity...
16 KB (1,932 words) - 03:16, 31 July 2024
Thomas–Fermi model (redirect from Thomas-Fermi theory)
atom is t ( r ) = ∫ p 2 2 m e n ( r ) F r ( p ) d p = n ( r ) ∫ 0 p f ( r ) p 2 2 m e 4 π p 2 4 3 π p F 3 ( r ) d p = C k i n [ n ( r ) ]...
15 KB (2,499 words) - 13:30, 26 July 2024
theory — Perturbation theory — Potential theory — Probability theory — Ramsey theory — Rational choice theory — Representation theory — Ring theory —...
38 KB (4,356 words) - 13:30, 30 July 2024
straightforwardly defined using the techniques of perturbation theory, but it is not known in general how to define string theory nonperturbatively. It is also not clear...
123 KB (15,355 words) - 13:02, 16 August 2024
Čížek used the correlation function of MET and used Goldstone-type perturbation theory to get the energy expression, while original MET was completely variational...
28 KB (4,353 words) - 18:46, 19 July 2024
Fermi's golden rule (category Perturbation theory)
standard way to derive the equation is to start with time-dependent perturbation theory and to take the limit for absorption under the assumption that the...
31 KB (3,936 words) - 02:26, 14 August 2024
are lower order terms of the Luttinger–Kohn k·p perturbation theory in powers of k {\displaystyle k} . Next terms of this expansion also produce terms...
28 KB (4,302 words) - 23:55, 25 June 2024
approach, interactions between different atomic sites are considered as perturbations. There exist several kinds of interactions we must consider. The crystal...
34 KB (7,311 words) - 20:02, 6 February 2024
Complete active space perturbation theory (CASPTn) is a multireference electron correlation method for computational investigation of molecular systems...
5 KB (664 words) - 12:32, 13 August 2023
configuration interaction (MRCI) or multi-reference perturbation theories like complete active space perturbation theory (CASPT2). These methods can deal with extremely...
8 KB (1,118 words) - 19:07, 14 November 2023
Statistical associating fluid theory (SAFT) is a chemical theory, based on perturbation theory, that uses statistical thermodynamics to explain how complex...
16 KB (1,568 words) - 17:02, 13 August 2024
variety of theoretical methods including density functional theory, k·p perturbation theory, and others are used to supplement and support the various...
26 KB (3,717 words) - 20:05, 25 March 2024