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Recent developments in symmetry‐adapted perturbation theory
Wiley Interdisciplinary Reviews: Computational Molecular Science, 2020Symmetry‐adapted perturbation theory (SAPT) is a well‐established method to compute accurate intermolecular interaction energies in terms of physical effects such as electrostatics, induction (polarization), dispersion, and exchange.
K. Patkowski
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Symmetry in Inorganic and Coordination Compounds, 2021
Abstract This chapter provides a general description of perturbation theory in terms of Feynman diagrams. The general prescriptions of constructing Feynman diagrams in momentum space are given, including for an S-matrix. The connected Green functions and the corresponding generation functional are defined with full proofs.
F. Morazzoni
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Abstract This chapter provides a general description of perturbation theory in terms of Feynman diagrams. The general prescriptions of constructing Feynman diagrams in momentum space are given, including for an S-matrix. The connected Green functions and the corresponding generation functional are defined with full proofs.
F. Morazzoni
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World Scientific Lecture Notes in Physics, 2020
Maolin Che, Yimin Wei
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Maolin Che, Yimin Wei
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Semigroups of Linear Operators, 2019
This chapter examines applications drawn from perturbation theory. The main topic in perturbation theory is the energy and spontaneous decay rate of the 21-cm hyperfine line in atomic hydrogen. Before there were electronic computers, people had quite an accurate theoretical understanding of the energy levels in helium and more complicated systems.
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This chapter examines applications drawn from perturbation theory. The main topic in perturbation theory is the energy and spontaneous decay rate of the 21-cm hyperfine line in atomic hydrogen. Before there were electronic computers, people had quite an accurate theoretical understanding of the energy levels in helium and more complicated systems.
semanticscholar +3 more sources
Black hole perturbation theory and gravitational self-force
, 2021Much of the success of gravitational-wave astronomy rests on perturbation theory. Historically, perturbative analysis of gravitational-wave sources has largely focused on post-Newtonian theory.
A. Pound, B. Wardell
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Perturbation Theory Approach to Intermolecular Potential Energy Surfaces of van der Waals Complexes
Chemical Reviews, 1994B. Jeziorski, R. Moszynski, K. Szalewicz
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The Journal of Chemical Physics, 2015
Despite the fundamental importance of electron density in density functional theory, perturbations are still usually dealt with using Hartree-Fock-like orbital equations known as coupled-perturbed Kohn-Sham (CPKS). As an alternative, we develop a perturbation theory that solves for the perturbed density directly, removing the need for CPKS.
Mark C. Palenik, Brett I. Dunlap
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Despite the fundamental importance of electron density in density functional theory, perturbations are still usually dealt with using Hartree-Fock-like orbital equations known as coupled-perturbed Kohn-Sham (CPKS). As an alternative, we develop a perturbation theory that solves for the perturbed density directly, removing the need for CPKS.
Mark C. Palenik, Brett I. Dunlap
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1984
In perturbation theory one relates the properties (e.g. the distribution functions or free energy) of the real system, for which the intermolecular potential energy is u(rN ωN), to those of a reference system where the potential is u0(rNωN), usually by an expansion in powers of the perturbation potential u1 ≡ u — u0. The first-order, second-order, etc.
C. G. Gray, K. E. Gubbins
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In perturbation theory one relates the properties (e.g. the distribution functions or free energy) of the real system, for which the intermolecular potential energy is u(rN ωN), to those of a reference system where the potential is u0(rNωN), usually by an expansion in powers of the perturbation potential u1 ≡ u — u0. The first-order, second-order, etc.
C. G. Gray, K. E. Gubbins
openaire +1 more source