Category:Constrained-random-phase approximation: Difference between revisions

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The '''constrained random-phase approximation''' (CRPA) is a method that allows the calculation of the effective interaction parameter U, J, and J' for model Hamiltonians.  
 
The main idea is to neglect the screening effects of specific '''target states''' in the screened Coulomb interaction W of the [[The GW approximation of Hedin's equations|GW method]].  
== Theoretical Background ==
The resulting partially screened Coulomb interaction is evaluated in a [[Wannier functions|localized basis]] that spans the target space and is described by the model Hamiltonian.  
The constrained random-phase approximation (CRPA) is a method that allows to calculate the effective interaction parameter U, J and J' for model Hamiltonians.  
The target space is usually low-dimensional and therefore allows for the application of a higher-level theory, such as dynamical-mean-field theory (DMFT).
The main idea is to neglect screening effects of specific '''target states''' in the screened Coulomb interaction W of the [[The GW approximation of Hedin's equations|GW method]].  
The resulting partially screened Coulomb interaction is usually evaluated in a localized basis that spans the target space and is described by the model Hamiltonian.  
The target space is usually low-dimensional and therefore allows for the application of a higher level theory, such as dynamical mean field theory.


More information about CRPA is found on the following page:
More information about CRPA is found on the following page:


[[Constrained–random-phase–approximation_formalism]]
[[Constrained–random-phase–approximation_formalism]]
== How to ==
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[[Category:VASP|ACFDT]][[Category:Many-body perturbation theory]][[Category:VASP6]]
[[Category:VASP|ACFDT]][[Category:Many-body perturbation theory]][[Category:VASP6]]

Revision as of 12:54, 19 July 2022

The constrained random-phase approximation (CRPA) is a method that allows the calculation of the effective interaction parameter U, J, and J' for model Hamiltonians. The main idea is to neglect the screening effects of specific target states in the screened Coulomb interaction W of the GW method. The resulting partially screened Coulomb interaction is evaluated in a localized basis that spans the target space and is described by the model Hamiltonian. The target space is usually low-dimensional and therefore allows for the application of a higher-level theory, such as dynamical-mean-field theory (DMFT).

More information about CRPA is found on the following page:

Constrained–random-phase–approximation_formalism

Pages in category "Constrained-random-phase approximation"

The following 7 pages are in this category, out of 7 total.