dmft_tools.initial_self_energies

Contains all functions related to determining the double counting and the initial self-energy.

dmft_tools.initial_self_energies._dc_orb_shift_per_shell(sum_k, dc_orb_shift)

Splits the flat dc_orb_shift input into one array per inequivalent shell

dmft_tools.initial_self_energies._load_sigma_from_h5(h5_archive, iteration)

Reads impurity self-energy for all impurities from file and returns them as a list

Parameters:

h5_archiveHDFArchive

HDFArchive to read from

iterationint

at which iteration will sigma be loaded

Returns:

self_energieslist of green functions

dc_impnumpy array

DC potentials

dc_energynumpy array

DC energies per impurity

density_matrixnumpy arrays

Density matrix from the previous self-energy

dmft_tools.initial_self_energies._set_loaded_sigma(sum_k, loaded_sigma, loaded_dc_imp, general_params)

Adjusts for the Hartree shift when loading a self energy Sigma_freq from a previous calculation that was run with a different U, J or double counting.

Parameters:

sum_kSumkDFT object

Sumk object with the information about the correct block structure

loaded_sigmalist of BlockGf (Green’s function) objects

List of Sigmas loaded from the previous calculation

loaded_dc_implist of dicts

List of dicts containing the loaded DC. Used to adjust the Hartree shift.

general_paramsdict

general parameters as a dict

Returns:

start_sigmalist of BlockGf (Green’s function) objects

List of Sigmas, loaded Sigma adjusted for the new Hartree term

Raises:

ValueError

Raised if the block structure between the loaded and the Sumk DC_imp does not agree.

dmft_tools.initial_self_energies._sumk_sigma_to_solver_struct(sum_k, start_sigma)

Extracts the local Sigma. Copied from SumkDFT.extract_G_loc, version 2.1.x.

Parameters:

sum_kSumkDFT object

Sumk object with the information about the correct block structure

start_sigmalist of BlockGf (Green’s function) objects

List of Sigmas in sum_k block structure that are to be converted.

Returns:

Sigma_inequivlist of BlockGf (Green’s function) objects

List of Sigmas that can be used to initialize the solver

dmft_tools.initial_self_energies.calculate_double_counting(sum_k, density_matrix, general_params, gw_params, advanced_params, solver_type_per_imp, G_loc_all=None)

Calculates the double counting, including all manipulations from advanced_params.

Parameters:

sum_kSumkDFT object

density_matrixlist of gf_struct_solver like

List of density matrices for all inequivalent shells

general_paramsdict

general parameters as a dict

gw_paramsdict

GW parameters as a dict

advanced_paramsdict

advanced parameters as a dict

solver_type_per_implist of str

List of solver types for each impurity

G_loc_alllist of BlockGf (Green’s function) objects, optional

List of local Green’s functions for all shells

Returns:

sum_kSumKDFT object

The SumKDFT object containing the updated double counting

dmft_tools.initial_self_energies.determine_dc_and_initial_sigma(general_params, gw_params, advanced_params, sum_k, archive, iteration_offset, G_loc_all, solvers, solver_type_per_imp)

Determines the double counting (DC) and the initial Sigma. This can happen in five different ways: * Calculation resumed: use the previous DC and the Sigma of the last complete calculation.

• Calculation initialized with load_sigma: use the DC and Sigma from the previous file. If the DC changed (and therefore the Hartree shift), the initial Sigma is adjusted by that.

• New calculation, with DC: calculate the DC, then initialize the Sigma as the DC, effectively starting the calculation from the DFT Green’s function. Also breaks magnetic symmetry if calculation is magnetic.

• New calculation, without DC: Sigma is initialized as 0, starting the calculation from the DFT Green’s function.

Parameters:

general_paramsdict

general parameters as a dict

gw_paramsdict

GW parameters as a dict

advanced_paramsdict

advanced parameters as a dict

sum_kSumkDFT object

Sumk object with the information about the correct block structure

archiveHDFArchive

the archive of the current calculation

iteration_offsetint

the iterations done before this calculation

G_loc_allGf

local Green function for all shells

solverslist

list of Solver instances

Returns:

sum_kSumkDFT object

the SumkDFT object, updated by the initial Sigma and the DC

solverslist

list of Solver instances, updated by the initial Sigma

dmft_tools.initial_self_energies.split_deg_shells_by_orb_shift(sum_k, advanced_params)

Lifts the degeneracies of the solver blocks that dc_orb_shift breaks.

The degenerate blocks are found from the DFT density matrix, before the shift is applied. Symmetrizing G0 over orbitals that are shifted differently would average the shift out of G0 while it stays in the impurity levels. Blocks remain degenerate only if their orbitals are shifted by the same amounts, so up and down stay together in a paramagnetic calculation.