LSCDM: Difference between revisions

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{{DEF|LSCDM|.FALSE.|}}
{{DEF|LSCDM|.FALSE.|}}


Description: {{TAG|LSCDM}} switches on the selected-columns-of-the-density-matrix (SCDM) method.  
Description: {{TAG|LSCDM}} switches on the selected columns of the density matrix (SCDM) method.  


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The selected columns of the density matrix {{TAG|LSCDM}} method works by fitting a unitary matrix <math>U_{mn\mathbf{k}}</math> that transforms from the Bloch states obtained by VASP to a [[Wannier Functions| Wannier basis]].
The SCDM method is implemented as proposed by A. Dale and L. Lin {{cite|dale:mms:2018}}.
The SCDM method is implemented as proposed by A. Dale and L. Lin {{cite|dale:mms:2018}}.
This is done using a [[Wannier_Functions#One-shot_single_value_decomposition (SVD) | one-shot method ]] through a singular-value decomposition (SVD).
In order to obtain a good Wannierization, a certain level of freedom should be given to the localized orbitals to adequately accommodate the Bloch states. This is controlled by the cutoff function specified by the {{TAG|CUTOFF_TYPE}} tag and related parameters
<math>\mu</math> ({{TAG|CUTOFF_MU}}) and
<math>\sigma</math> ({{TAG|CUTOFF_SIGMA}}).


== Related tags and articles==
== Related tags and articles==

Revision as of 09:38, 19 July 2022

LSCDM = .TRUE. | .FALSE. 

Default: LSCDM = .FALSE.

Description: LSCDM switches on the selected columns of the density matrix (SCDM) method.


The selected columns of the density matrix LSCDM method works by fitting a unitary matrix that transforms from the Bloch states obtained by VASP to a Wannier basis. The SCDM method is implemented as proposed by A. Dale and L. Lin . This is done using a one-shot method through a singular-value decomposition (SVD).

In order to obtain a good Wannierization, a certain level of freedom should be given to the localized orbitals to adequately accommodate the Bloch states. This is controlled by the cutoff function specified by the CUTOFF_TYPE tag and related parameters (CUTOFF_MU) and (CUTOFF_SIGMA).

Related tags and articles

CUTOFF_TYPE, CUTOFF_MU, CUTOFF_SIGMA

Examples that use this tag

References