triqs_dft_tools.sumk_dft_tools.SumkDFTTools.downfold

SumkDFTTools.downfold(ik, ish, bname, gf_to_downfold, gf_inp, shells='corr', ir=None)

Downfolds a block of the Green’s function for a given shell and k-point using the corresponding projector matrices.

Parameters:

ik : integer

k-point index for which the downfolding is to be done.

ish : integer

Shell index of GF to be downfolded.

  • if shells=’corr’: ish labels all correlated shells (equivalent or not)

  • if shells=’all’: ish labels only representative (inequivalent) non-correlated shells

bname : string

Block name of the target block of the lattice Green’s function.

gf_to_downfold : Gf

Block of the Green’s function that is to be downfolded.

gf_inp : Gf

FIXME

shells : string, optional

  • if shells=’corr’: orthonormalized projectors for correlated shells are used for the downfolding.

  • if shells=’all’: non-normalized projectors for all included shells are used for the downfolding.

  • if shells=’csc’: orthonormalized projectors for all shells are used for the downfolding. Used for H(k).

ir : integer, optional

Index of equivalent site in the non-correlated shell ‘ish’, only used if shells=’all’.

Returns:

gf_downfolded : Gf

Downfolded block of the lattice Green’s function.