Source code for doped.utils.parsing

"""
Helper functions for parsing VASP supercell defect calculations.
"""
import contextlib
import itertools
import os
import warnings
from typing import Optional, Union

import numpy as np
from monty.serialization import loadfn
from pymatgen.analysis.defects.core import DefectType
from pymatgen.core.structure import PeriodicSite, Structure
from pymatgen.io.vasp.inputs import UnknownPotcarWarning
from pymatgen.io.vasp.outputs import Locpot, Outcar, Vasprun
from pymatgen.util.coord import pbc_diff

from doped import _ignore_pmg_warnings
from doped.core import DefectEntry


[docs] def find_archived_fname(fname, raise_error=True): """ Find a suitable filename, taking account of possible use of compression software. """ if os.path.exists(fname): return fname # Check for archive files for ext in [".gz", ".xz", ".bz", ".lzma"]: if os.path.exists(fname + ext): return fname + ext if raise_error: raise FileNotFoundError return None
[docs] def get_vasprun(vasprun_path, **kwargs): """ Read the vasprun.xml(.gz) file as a pymatgen Vasprun object. """ vasprun_path = str(vasprun_path) # convert to string if Path object warnings.filterwarnings( "ignore", category=UnknownPotcarWarning ) # Ignore unknown POTCAR warnings when loading vasprun.xml # pymatgen assumes the default PBE with no way of changing this within get_vasprun()) warnings.filterwarnings( "ignore", message="No POTCAR file with matching TITEL fields" ) # `message` only needs to match start of message try: vasprun = Vasprun(find_archived_fname(vasprun_path), **kwargs) except FileNotFoundError as exc: raise FileNotFoundError( f"vasprun.xml or compressed version (.gz/.xz/.bz/.lzma) not found at {vasprun_path}(" f".gz/.xz/.bz/.lzma). Needed for parsing calculation output!" ) from exc return vasprun
[docs] def get_locpot(locpot_path): """ Read the LOCPOT(.gz) file as a pymatgen Locpot object. """ locpot_path = str(locpot_path) # convert to string if Path object try: locpot = Locpot.from_file(find_archived_fname(locpot_path)) except FileNotFoundError: raise FileNotFoundError( f"LOCPOT or compressed version not found at (.gz/.xz/.bz/.lzma) not found at {locpot_path}(" f".gz/.xz/.bz/.lzma). Needed for calculating the Freysoldt (FNV) image charge correction!" ) from None return locpot
[docs] def get_outcar(outcar_path): """ Read the OUTCAR(.gz) file as a pymatgen Outcar object. """ outcar_path = str(outcar_path) # convert to string if Path object try: outcar = Outcar(find_archived_fname(outcar_path)) except FileNotFoundError: raise FileNotFoundError( f"OUTCAR file not found at {outcar_path}. Needed for calculating the Kumagai (eFNV) " f"image charge correction." ) from None return outcar
def _get_output_files_and_check_if_multiple(output_file="vasprun.xml", path="."): """ Search for all files with filenames matching ``output_file``, case-insensitive. Returns (output file path, Multiple?) where Multiple is True if multiple matching files are found. """ files = os.listdir(path) output_files = [filename for filename in files if output_file.lower() in filename.lower()] # sort by direct match to {output_file}, direct match to {output_file}.gz, then alphabetically: if output_files := sorted( output_files, key=lambda x: (x == output_file, x == f"{output_file}.gz", x), reverse=True, ): output_path = os.path.join(path, output_files[0]) return (output_path, True) if len(output_files) > 1 else (output_path, False) return path, False # so when `get_X()` is called, it will raise an informative FileNotFoundError
[docs] def get_defect_type_and_composition_diff(bulk, defect): """ Get the difference in composition between a bulk structure and a defect structure. Contributed by Dr. Alex Ganose (@ Imperial Chemistry) and refactored for extrinsic species and code efficiency/robustness improvements. """ bulk_comp = bulk.composition.get_el_amt_dict() defect_comp = defect.composition.get_el_amt_dict() composition_diff = { element: int(defect_amount - bulk_comp.get(element, 0)) for element, defect_amount in defect_comp.items() if int(defect_amount - bulk_comp.get(element, 0)) != 0 } if len(composition_diff) == 1 and list(composition_diff.values())[0] == 1: defect_type = "interstitial" elif len(composition_diff) == 1 and list(composition_diff.values())[0] == -1: defect_type = "vacancy" elif len(composition_diff) == 2: defect_type = "substitution" else: raise RuntimeError( "Could not determine defect type from composition difference of bulk and defect structures." ) return defect_type, composition_diff
[docs] def get_defect_site_idxs_and_unrelaxed_structure( bulk, defect, defect_type, composition_diff, unique_tolerance=1 ): """ Get the defect site and unrelaxed structure, where 'unrelaxed structure' corresponds to the pristine defect supercell structure for vacancies / substitutions, and the pristine bulk structure with the `final` relaxed interstitial site for interstitials. Initially contributed by Dr. Alex Ganose (@ Imperial Chemistry) and refactored for extrinsic species and code efficiency/robustness improvements. Returns: bulk_site_idx: index of the site in the bulk structure that corresponds to the defect site in the defect structure defect_site_idx: index of the defect site in the defect structure unrelaxed_defect_structure: pristine defect supercell structure for vacancies/substitutions (i.e. pristine bulk with unrelaxed vacancy/ substitution), or the pristine bulk structure with the `final` relaxed interstitial site for interstitials. """ def process_substitution(bulk, defect, composition_diff): old_species = _get_species_from_composition_diff(composition_diff, -1) new_species = _get_species_from_composition_diff(composition_diff, 1) bulk_new_species_coords, _bulk_new_species_idx = get_coords_and_idx_of_species(bulk, new_species) defect_new_species_coords, defect_new_species_idx = get_coords_and_idx_of_species( defect, new_species ) if bulk_new_species_coords.size > 0: # intrinsic substitution # find coords of new species in defect structure, taking into account periodic boundaries defect_site_arg_idx = find_nearest_coords( bulk_new_species_coords[:, None], defect_new_species_coords, bulk.lattice.matrix, defect_type="substitution", searched_structure="defect", ) else: # extrinsic substitution defect_site_arg_idx = 0 # Get the coords and site index of the defect that was used in the VASP calculation defect_coords = defect_new_species_coords[defect_site_arg_idx] # frac coords of defect site defect_site_idx = defect_new_species_idx[defect_site_arg_idx] # now find the closest old_species site in the bulk structure to the defect site # again, make sure to use periodic boundaries bulk_old_species_coords, _bulk_old_species_idx = get_coords_and_idx_of_species(bulk, old_species) bulk_site_arg_idx = find_nearest_coords( bulk_old_species_coords, defect_coords, bulk.lattice.matrix, defect_type="substitution", searched_structure="bulk", ) # currently, original_site_idx is indexed with respect to the old species only. # need to get the index in the full structure: unrelaxed_defect_structure, bulk_site_idx = _remove_and_insert_species_from_bulk( bulk, bulk_old_species_coords, bulk_site_arg_idx, new_species, defect_site_idx, defect_type="substitution", searched_structure="bulk", ) return bulk_site_idx, defect_site_idx, unrelaxed_defect_structure def process_vacancy(bulk, defect, composition_diff): old_species = _get_species_from_composition_diff(composition_diff, -1) bulk_old_species_coords, _bulk_old_species_idx = get_coords_and_idx_of_species(bulk, old_species) defect_old_species_coords, _defect_old_species_idx = get_coords_and_idx_of_species( defect, old_species ) bulk_site_arg_idx = find_nearest_coords( bulk_old_species_coords[:, None], defect_old_species_coords, bulk.lattice.matrix, defect_type="vacancy", searched_structure="bulk", ) # currently, original_site_idx is indexed with respect to the old species only. # need to get the index in the full structure: defect_site_idx = None unrelaxed_defect_structure, bulk_site_idx = _remove_and_insert_species_from_bulk( bulk, bulk_old_species_coords, bulk_site_arg_idx, new_species=None, defect_site_idx=defect_site_idx, defect_type="vacancy", searched_structure="bulk", ) return bulk_site_idx, defect_site_idx, unrelaxed_defect_structure def process_interstitial(bulk, defect, composition_diff): new_species = _get_species_from_composition_diff(composition_diff, 1) bulk_new_species_coords, _bulk_new_species_idx = get_coords_and_idx_of_species(bulk, new_species) defect_new_species_coords, defect_new_species_idx = get_coords_and_idx_of_species( defect, new_species ) if bulk_new_species_coords.size > 0: # intrinsic interstitial defect_site_arg_idx = find_nearest_coords( bulk_new_species_coords[:, None], defect_new_species_coords, bulk.lattice.matrix, defect_type="interstitial", searched_structure="defect", ) else: # extrinsic interstitial defect_site_arg_idx = 0 # Get the coords and site index of the defect that was used in the VASP calculation defect_site_coords = defect_new_species_coords[defect_site_arg_idx] # frac coords of defect site defect_site_idx = defect_new_species_idx[defect_site_arg_idx] # currently, original_site_idx is indexed with respect to the old species only. # need to get the index in the full structure: unrelaxed_defect_structure, bulk_site_idx = _remove_and_insert_species_from_bulk( bulk, coords=defect_site_coords, site_arg_idx=None, new_species=new_species, defect_site_idx=defect_site_idx, defect_type="interstitial", searched_structure="defect", ) return bulk_site_idx, defect_site_idx, unrelaxed_defect_structure handlers = { "substitution": process_substitution, "vacancy": process_vacancy, "interstitial": process_interstitial, } if defect_type not in handlers: raise ValueError(f"Invalid defect type: {defect_type}") return handlers[defect_type](bulk, defect, composition_diff)
def _get_species_from_composition_diff(composition_diff, el_change): """ Get the species corresponding to the given change in composition. """ return [el for el, amt in composition_diff.items() if amt == el_change][0]
[docs] def get_coords_and_idx_of_species(structure, species_name): """ Get arrays of the coordinates and indices of the given species in the structure. """ coords = [] idx = [] for i, site in enumerate(structure): if site.specie.symbol == species_name: coords.append(site.frac_coords) idx.append(i) return np.array(coords), np.array(idx)
[docs] def find_nearest_coords( bulk_coords, target_coords, bulk_lattice_matrix, defect_type="substitution", searched_structure="bulk", unique_tolerance=1, ): """ Find the nearest coords in bulk_coords to target_coords. """ distance_matrix = np.linalg.norm( np.dot(pbc_diff(bulk_coords, target_coords), bulk_lattice_matrix), axis=-1 ) site_matches = distance_matrix.argmin(axis=0 if defect_type == "vacancy" else -1) def _site_matching_failure_error(defect_type, searched_structure): raise RuntimeError( f"Could not uniquely determine site of {defect_type} in {searched_structure} " f"structure. Remember the bulk and defect supercells should have the same " f"definitions/basis sets for site-matching (parsing) to be possible." ) if len(site_matches.shape) == 1: if len(np.unique(site_matches)) != len(site_matches): _site_matching_failure_error(defect_type, searched_structure) return list( set(np.arange(max(bulk_coords.shape[0], target_coords.shape[0]), dtype=int)) - set(site_matches) )[0] if len(site_matches.shape) == 0: # if there are any other matches with a distance within unique_tolerance of the located site # then unique matching failed if len(distance_matrix[distance_matrix < distance_matrix[site_matches] * unique_tolerance]) > 1: _site_matching_failure_error(defect_type, searched_structure) return site_matches return None
def _remove_and_insert_species_from_bulk( bulk, coords, site_arg_idx, new_species, defect_site_idx, defect_type="substitution", searched_structure="bulk", unique_tolerance=1, ): # currently, original_site_idx is indexed with respect to the old species only. # need to get the index in the full structure: unrelaxed_defect_structure = bulk.copy() # create unrelaxed defect structure bulk_coords = np.array([s.frac_coords for s in bulk]) bulk_site_idx = None if site_arg_idx is not None: bulk_site_idx = find_nearest_coords( bulk_coords, coords[site_arg_idx], bulk.lattice.matrix, defect_type=defect_type, searched_structure=searched_structure, unique_tolerance=unique_tolerance, ) unrelaxed_defect_structure.remove_sites([bulk_site_idx]) defect_coords = bulk_coords[bulk_site_idx] else: defect_coords = coords # Place defect in same location as output from DFT if defect_site_idx is not None: unrelaxed_defect_structure.insert(defect_site_idx, new_species, defect_coords) return unrelaxed_defect_structure, bulk_site_idx
[docs] def check_atom_mapping_far_from_defect(bulk, defect, defect_coords): """ Check the displacement of atoms far from the determined defect site, and warn the user if they are large (often indicates a mismatch between the bulk and defect supercell definitions). """ # suppress pydefect INFO messages import logging from vise import user_settings user_settings.logger.setLevel(logging.CRITICAL) from pydefect.cli.vasp.make_efnv_correction import calc_max_sphere_radius # vise suppresses `UserWarning`s, so need to reset warnings.simplefilter("default") warnings.filterwarnings("ignore", message="`np.int` is a deprecated alias for the builtin `int`") warnings.filterwarnings("ignore", message="Use get_magnetic_symmetry()") _ignore_pmg_warnings() far_from_defect_disps = {site.specie.symbol: [] for site in bulk} wigner_seitz_radius = calc_max_sphere_radius(bulk.lattice.matrix) bulk_sites_outside_or_at_wigner_radius = [ site for site in bulk if site.distance_and_image_from_frac_coords(defect_coords)[0] > np.max((wigner_seitz_radius - 1, 1)) ] bulk_species_coord_dict = {} for species in bulk.composition.elements: # avoid recomputing coords for each site bulk_species_coords, _bulk_new_species_idx = get_coords_and_idx_of_species( bulk_sites_outside_or_at_wigner_radius, species.name ) bulk_species_coord_dict[species.name] = bulk_species_coords for site in defect: if site.distance_and_image_from_frac_coords(defect_coords)[0] > wigner_seitz_radius: bulk_site_arg_idx = find_nearest_coords( # get closest site in bulk to defect site bulk_species_coord_dict[site.specie.symbol], site.frac_coords, bulk.lattice.matrix, defect_type="substitution", searched_structure="bulk", ) far_from_defect_disps[site.specie.symbol].append( round( site.distance_and_image_from_frac_coords( bulk_species_coord_dict[site.specie.symbol][bulk_site_arg_idx] )[0], 2, ) ) if far_from_defect_large_disps := { specie: list for specie, list in far_from_defect_disps.items() if list and np.mean(list) > 0.5 }: warnings.warn( f"Detected atoms far from the defect site (>{wigner_seitz_radius:.2f} Å) with major " f"displacements (>0.5 Å) in the defect supercell. This likely indicates a mismatch " f"between the bulk and defect supercell definitions or an unconverged supercell size, " f"both of which could cause errors in parsing. The mean displacement of the following " f"species, at sites far from the determined defect position, is >0.5 Å: " f"{list(far_from_defect_large_disps.keys())}, with displacements (Å): " f"{far_from_defect_large_disps}" )
[docs] def get_site_mapping_indices(structure_a: Structure, structure_b: Structure, threshold=2.0): """ Reset the position of a partially relaxed structure to its unrelaxed positions. The template structure may have a different species ordering to the ``input_structure``. NOTE: This assumes that both structures have the same lattice definitions (i.e. that they match, and aren't rigidly translated/rotated with respect to each other), which is mostly the case unless we have a mismatching defect/bulk supercell (in which case the ``check_atom_mapping_far_from_defect`` warning should be thrown anyway during parsing). Currently this function is only used for analysing site displacements in the ``displacements`` module so this is fine (user will already have been warned at this point if there is a possible mismatch). """ ## Generate a site matching table between the input and the template min_dist_with_index = [] all_input_fcoords = [list(site.frac_coords.round(3)) for site in structure_a] all_template_fcoords = [list(site.frac_coords.round(3)) for site in structure_b] for species in structure_a.composition.elements: input_fcoords = [ list(site.frac_coords.round(3)) for site in structure_a if site.specie.symbol == species.symbol ] template_fcoords = [ list(site.frac_coords.round(3)) for site in structure_b if site.specie.symbol == species.symbol ] dmat = structure_a.lattice.get_all_distances(input_fcoords, template_fcoords) for index, coords in enumerate(all_input_fcoords): if coords in input_fcoords: dists = dmat[input_fcoords.index(coords)] current_dist = dists.min() template_fcoord = template_fcoords[dists.argmin()] template_index = all_template_fcoords.index(template_fcoord) min_dist_with_index.append( [ current_dist, index, template_index, ] ) if current_dist > threshold: site_a = structure_a[index] site_b = structure_b[template_index] warnings.warn( f"Large site displacement {current_dist:.2f} Å detected when matching atomic " f"sites: {site_a} -> {site_b}." ) return min_dist_with_index
[docs] def reorder_s1_like_s2(s1_structure: Structure, s2_structure: Structure, threshold=5.0): """ Reorder the atoms of a (relaxed) structure, s1, to match the ordering of the atoms in s2_structure. s1/s2 structures may have a different species orderings. Previously used to ensure correct site matching when pulling site potentials for the eFNV Kumagai correction, though no longer used for this purpose. If threshold is set to a low value, it will raise a warning if there is a large site displacement detected. NOTE: This assumes that both structures have the same lattice definitions (i.e. that they match, and aren't rigidly translated/rotated with respect to each other), which is mostly the case unless we have a mismatching defect/bulk supercell (in which case the ``check_atom_mapping_far_from_defect`` warning should be thrown anyway during parsing). Currently this function is no longer used, but if it is reintroduced at any point, this point should be noted! """ # Obtain site mapping between the initial_relax_structure and the unrelaxed structure mapping = get_site_mapping_indices(s2_structure, s1_structure, threshold=threshold) # Reorder s1_structure so that it matches the ordering of s2_structure reordered_sites = [s1_structure[tmp[2]] for tmp in mapping] # avoid warning about selective_dynamics properties (can happen if user explicitly set "T T T" (or # otherwise) for the bulk): warnings.filterwarnings("ignore", message="Not all sites have property") new_structure = Structure.from_sites(reordered_sites) assert len(new_structure) == len(s1_structure) return new_structure
def _compare_potcar_symbols( bulk_potcar_symbols, defect_potcar_symbols, bulk_name="bulk", defect_name="defect" ): """ Check all POTCAR symbols in the bulk are the same in the defect calculation. Returns True if the symbols match, otherwise returns a list of the symbols for the bulk and defect calculations. """ for symbol in bulk_potcar_symbols: if symbol["titel"] not in [symbol["titel"] for symbol in defect_potcar_symbols]: warnings.warn( f"The POTCAR symbols for your {bulk_name} and {defect_name} calculations do not match, " f"which is likely to cause severe errors in the parsed results. Found the following " f"symbol in the {bulk_name} calculation:" f"\n{symbol['titel']}\n" f"but not in the {defect_name} calculation:" f"\n{[symbol['titel'] for symbol in defect_potcar_symbols]}\n" f"The same POTCAR settings should be used for all calculations for accurate results!" ) return [bulk_potcar_symbols, defect_potcar_symbols] return True def _compare_kpoints( bulk_actual_kpoints, defect_actual_kpoints, bulk_kpoints=None, defect_kpoints=None, bulk_name="bulk", defect_name="defect", ): """ Check bulk and defect KPOINTS are the same, using the Vasprun.actual_kpoints lists (i.e. the VASP IBZKPTs essentially). Returns True if the KPOINTS match, otherwise returns a list of the KPOINTS for the bulk and defect calculations. """ # sort kpoints, in case same KPOINTS just different ordering: sorted_bulk_kpoints = sorted(np.array(bulk_actual_kpoints), key=tuple) sorted_defect_kpoints = sorted(np.array(defect_actual_kpoints), key=tuple) actual_kpoints_eq = len(sorted_bulk_kpoints) == len(sorted_defect_kpoints) and np.allclose( sorted_bulk_kpoints, sorted_defect_kpoints ) # if different symmetry settings used (e.g. for bulk), actual_kpoints can differ but are the same # input kpoints, which we assume is fine: kpoints_eq = bulk_kpoints.kpts == defect_kpoints.kpts if bulk_kpoints and defect_kpoints else True if not (actual_kpoints_eq or kpoints_eq): warnings.warn( f"The KPOINTS for your {bulk_name} and {defect_name} calculations do not match, which is " f"likely to cause errors in the parsed results. Found the following KPOINTS in the " f"{bulk_name} calculation:" f"\n{sorted_bulk_kpoints}\n" f"and in the {defect_name} calculation:" f"\n{sorted_defect_kpoints}\n" f"In general, the same KPOINTS settings should be used for all final calculations for " f"accurate results!" ) return [sorted_bulk_kpoints, sorted_defect_kpoints] return True def _compare_incar_tags( bulk_incar_dict, defect_incar_dict, fatal_incar_mismatch_tags=None, bulk_name="bulk", defect_name="defect", ): """ Check bulk and defect INCAR tags (that can affect energies) are the same. Returns True if no mismatching tags are found, otherwise returns a list of the mismatching tags. """ if fatal_incar_mismatch_tags is None: fatal_incar_mismatch_tags = { # dict of tags that can affect energies and their defaults "AEXX": 0.25, # default 0.25 "ENCUT": 0, "LREAL": False, # default False "HFSCREEN": 0, # default 0 (None) "GGA": "PE", # default PE "LHFCALC": False, # default False "ADDGRID": False, # default False "ISIF": 2, "LASPH": False, # default False "PREC": "Normal", # default Normal "PRECFOCK": "Normal", # default Normal "LDAU": False, # default False } def _compare_incar_vals(val1, val2): if isinstance(val1, str): return val1.split()[0].lower() == val2.split()[0].lower() if isinstance(val1, float): return np.isclose(val1, val2, rtol=1e-3) return val1 == val2 mismatch_list = [] for key, val in bulk_incar_dict.items(): if key in fatal_incar_mismatch_tags: defect_val = defect_incar_dict.get(key, fatal_incar_mismatch_tags[key]) if not _compare_incar_vals(val, defect_val): mismatch_list.append((key, val, defect_val)) # get any missing keys: defect_incar_keys_not_in_bulk = set(defect_incar_dict.keys()) - set(bulk_incar_dict.keys()) for key in defect_incar_keys_not_in_bulk: if key in fatal_incar_mismatch_tags and not _compare_incar_vals( defect_incar_dict[key], fatal_incar_mismatch_tags[key] ): mismatch_list.append((key, fatal_incar_mismatch_tags[key], defect_incar_dict[key])) if mismatch_list: # compare to defaults: warnings.warn( f"There are mismatching INCAR tags for your {bulk_name} and {defect_name} calculations which " f"are likely to cause errors in the parsed results (energies). Found the following " f"differences:\n" f"(in the format: (INCAR tag, value in {bulk_name} calculation, value in {defect_name} " f"calculation)):" f"\n{mismatch_list}\n" f"In general, the same INCAR settings should be used in all final calculations for these tags " f"which can affect energies!" ) return mismatch_list return True
[docs] def get_neutral_nelect_from_vasprun(vasprun: Vasprun, skip_potcar_init: bool = False) -> Union[int, float]: """ Determine the number of electrons (NELECT) from a Vasprun object, corresponding to a neutral charge state for the structure. """ from pymatgen.io.vasp.inputs import POTCAR_STATS_PATH potcar_summary_stats = loadfn(POTCAR_STATS_PATH) # for auto-charge determination nelect = None if not skip_potcar_init: with contextlib.suppress(Exception): # try determine charge without POTCARs first: grouped_symbols = [list(group) for key, group in itertools.groupby(vasprun.atomic_symbols)] for trial_functional in ["PBE_64", "PBE_54", "PBE_52", "PBE", potcar_summary_stats.keys()]: if all( potcar_summary_stats[trial_functional].get( vasprun.potcar_spec[i]["titel"].replace(" ", ""), False ) for i in range(len(grouped_symbols)) ): break nelect = sum( # this is always the NELECT for the bulk np.array([len(i) for i in grouped_symbols]) * np.array( [ potcar_summary_stats[trial_functional][ vasprun.potcar_spec[i]["titel"].replace(" ", "") ][0]["ZVAL"] for i in range(len(grouped_symbols)) ] ) ) if nelect is not None: return nelect # else try reverse engineer NELECT using DefectDictSet from doped.vasp import DefectDictSet potcar_symbols = [titel.split()[1] for titel in vasprun.potcar_symbols] potcar_settings = {symbol.split("_")[0]: symbol for symbol in potcar_symbols} with warnings.catch_warnings(): # ignore POTCAR warnings if not available warnings.simplefilter("ignore", UserWarning) return DefectDictSet( vasprun.structures[-1], charge_state=0, user_potcar_settings=potcar_settings, ).nelect
[docs] def get_interstitial_site_and_orientational_degeneracy( interstitial_defect_entry: DefectEntry, dist_tol: float = 0.15 ) -> int: """ Get the combined site and orientational degeneracy of an interstitial defect entry. The standard approach of using ``_get_equiv_sites()`` for interstitial site multiplicity and then ``point_symmetry_from_defect_entry()`` & ``get_orientational_degeneracy`` for symmetry/orientational degeneracy is preferred (as used in the ``DefectParser`` code), but alternatively this function can be used to compute the product of the site and orientational degeneracies. This is done by determining the number of equivalent sites in the bulk supercell for the given interstitial site (from defect_supercell_site), which gives the combined site and orientational degeneracy `if` there was no relaxation of the bulk lattice atoms. This matches the true combined degeneracy in most cases, except for split-interstitial type defects etc, where this would give an artificially high degeneracy (as, for example, the interstitial site is automatically assigned to one of the split-interstitial atoms and not the midpoint, giving a doubled degeneracy as it considers the two split-interstitial sites as two separate (degenerate) interstitial sites, instead of one). This is counteracted by dividing by the number of sites which are present in the defect supercell (within a distance tolerance of dist_tol in Å) with the same species, ensuring none of the predicted `different` equivalent sites are actually `included` in the defect structure. Args: interstitial_defect_entry: DefectEntry object for the interstitial defect. dist_tol: distance tolerance in Å for determining equivalent sites. Returns: combined site and orientational degeneracy of the interstitial defect entry (int). """ from doped.utils.symmetry import _get_all_equiv_sites if interstitial_defect_entry.bulk_entry is None: raise ValueError( "bulk_entry must be set for interstitial_defect_entry to determine the site and orientational " "degeneracies! (i.e. must be a parsed DefectEntry)" ) equiv_sites = _get_all_equiv_sites( _get_defect_supercell_bulk_site_coords(interstitial_defect_entry), _get_bulk_supercell(interstitial_defect_entry), ) equiv_sites_array = np.array([site.frac_coords for site in equiv_sites]) defect_supercell_sites_of_same_species_array = np.array( [ site.frac_coords for site in _get_defect_supercell(interstitial_defect_entry) if site.specie.symbol == interstitial_defect_entry.defect.site.specie.symbol ] ) distance_matrix = np.linalg.norm( np.dot( pbc_diff(defect_supercell_sites_of_same_species_array[:, None], equiv_sites_array), _get_bulk_supercell(interstitial_defect_entry).lattice.matrix, ), axis=-1, ) return len(equiv_sites) // len(distance_matrix[distance_matrix < dist_tol])
[docs] def get_orientational_degeneracy( defect_entry: Optional[DefectEntry] = None, relaxed_point_group: Optional[str] = None, bulk_site_point_group: Optional[str] = None, bulk_symm_ops: Optional[list] = None, defect_symm_ops: Optional[list] = None, symprec: float = 0.2, defect_type: Optional[Union[DefectType, str]] = None, ) -> float: r""" Get the orientational degeneracy factor for a given `relaxed` DefectEntry, by supplying either the DefectEntry object or the bulk-site & relaxed defect point group symbols (e.g. "Td", "C3v" etc). If a DefectEntry is supplied (and the point group symbols are not), this is computed by determining the `relaxed` defect point symmetry and the (unrelaxed) bulk site symmetry, and then getting the ratio of their point group orders (equivalent to the ratio of partition functions or number of symmetry operations (i.e. degeneracy)). For interstitials, the bulk site symmetry corresponds to the point symmetry of the interstitial site with `no relaxation of the host structure`, while for vacancies/substitutions it is simply the symmetry of their corresponding bulk site. This corresponds to the point symmetry of ``DefectEntry.defect``, or ``calculation_metadata["bulk_site"]/["unrelaxed_defect_structure"]``. Note: This tries to use the defect_entry.defect_supercell to determine the `relaxed` site symmetry. However, it should be noted that this is not guaranteed to work in all cases; namely for non-diagonal supercell expansions, or sometimes for non-scalar supercell expansion matrices (e.g. a 2x1x2 expansion)(particularly with high-symmetry materials) which can mess up the periodicity of the cell. ``doped`` tries to automatically check if this is the case, and will warn you if so. This can also be checked by using this function on your doped `generated` defects: .. code-block:: python from doped.generation import get_defect_name_from_entry for defect_name, defect_entry in defect_gen.items(): print(defect_name, get_defect_name_from_entry(defect_entry, relaxed=False), get_defect_name_from_entry(defect_entry), "\n") And if the point symmetries match in each case, then using this function on your parsed `relaxed` DefectEntry objects should correctly determine the final relaxed defect symmetry (and orientational degeneracy) - otherwise periodicity-breaking prevents this. If periodicity-breaking prevents auto-symmetry determination, you can manually determine the relaxed defect and bulk-site point symmetries, and/or orientational degeneracy, from visualising the structures (e.g. using VESTA)(can use ``get_orientational_degeneracy`` to obtain the corresponding orientational degeneracy factor for given defect/bulk-site point symmetries) and setting the corresponding values in the ``calculation_metadata['relaxed point symmetry']/['bulk site symmetry']`` and/or ``degeneracy_factors['orientational degeneracy']`` attributes. Note that the bulk-site point symmetry corresponds to that of ``DefectEntry.defect``, or equivalently ``calculation_metadata["bulk_site"]/["unrelaxed_defect_structure"]``, which for vacancies/substitutions is the symmetry of the corresponding bulk site, while for interstitials it is the point symmetry of the `final relaxed` interstitial site when placed in the (unrelaxed) bulk structure. The degeneracy factor is used in the calculation of defect/carrier concentrations and Fermi level behaviour (see e.g. doi.org/10.1039/D2FD00043A & doi.org/10.1039/D3CS00432E). Args: defect_entry (DefectEntry): DefectEntry object. (Default = None) relaxed_point_group (str): Point group symmetry (e.g. "Td", "C3v" etc) of the `relaxed` defect structure, if already calculated / manually determined. Default is None (automatically calculated by doped). bulk_site_point_group (str): Point group symmetry (e.g. "Td", "C3v" etc) of the defect site in the bulk, if already calculated / manually determined. For vacancies/substitutions, this should match the site symmetry label from ``doped`` when generating the defect, while for interstitials it should be the point symmetry of the `final relaxed` interstitial site, when placed in the bulk structure. Default is None (automatically calculated by doped). bulk_symm_ops (list): List of symmetry operations of the defect_entry.bulk_supercell structure (used in determining the `unrelaxed` bulk site symmetry), to avoid re-calculating. Default is None (recalculates). defect_symm_ops (list): List of symmetry operations of the defect_entry.defect_supercell structure (used in determining the `relaxed` point symmetry), to avoid re-calculating. Default is None (recalculates). symprec (float): Symmetry tolerance for spglib. Default is 0.2, which is larger than that used for only unrelaxed structures in doped (0.01), to account for residual structural noise in relaxed supercells. You may want to adjust for your system (e.g. if there are very slight octahedral distortions etc). defect_type (DefectType or str): The type of defect (e.g. Vacancy/"vacancy", Substitution/"substitution", Interstitial/"interstitial") to check if the output orientational degeneracy is reasonable (i.e. can only be less than 1 for interstitials). Default is None (no check). Returns: float: orientational degeneracy factor for the defect. """ from doped.utils.symmetry import group_order_from_schoenflies, point_symmetry_from_defect_entry if defect_entry is None: if relaxed_point_group is None or bulk_site_point_group is None: raise ValueError( "Either the DefectEntry or both defect and bulk site point group symbols must be " "provided for doped to determine the orientational degeneracy! " ) elif defect_entry.bulk_entry is None: raise ValueError( "bulk_entry must be set for defect_entry to determine the (relaxed) orientational degeneracy! " "(i.e. must be a parsed DefectEntry)" ) else: pass if relaxed_point_group is None: # this will throw warning if auto-detected that supercell breaks trans symmetry relaxed_point_group = point_symmetry_from_defect_entry( defect_entry, # type: ignore symm_ops=defect_symm_ops, # defect not bulk symm_ops symprec=symprec, relaxed=True, # relaxed ) if bulk_site_point_group is None: bulk_site_point_group = point_symmetry_from_defect_entry( defect_entry, # type: ignore symm_ops=bulk_symm_ops, # bulk not defect symm_ops symprec=symprec, # same symprec as relaxed_point_group for consistency relaxed=False, # unrelaxed ) # actually fine for split-vacancies (e.g. Ke's V_Sb in Sb2O5), or antisite-swaps etc: # (so avoid warning for now; user will be warned anyway if symmetry determination failing) # if orientational_degeneracy < 1 and not ( # defect_type == DefectType.Interstitial # or (isinstance(defect_type, str) and defect_type.lower() == "interstitial") # ): # raise ValueError( # f"From the input/determined point symmetries, an orientational degeneracy factor of " # f"{orientational_degeneracy} is predicted, which is less than 1, which is not reasonable " # f"for vacancies/substitutions, indicating an error in the symmetry determination!" # ) return group_order_from_schoenflies(bulk_site_point_group) / group_order_from_schoenflies( relaxed_point_group )
def _get_bulk_supercell(defect_entry: DefectEntry): if hasattr(defect_entry, "bulk_supercell") and defect_entry.bulk_supercell: return defect_entry.bulk_supercell if ( hasattr(defect_entry, "bulk_entry") and defect_entry.bulk_entry and hasattr(defect_entry.bulk_entry, "structure") and defect_entry.bulk_entry.structure ): return defect_entry.bulk_entry.structure return None def _get_defect_supercell(defect_entry: DefectEntry): if hasattr(defect_entry, "defect_supercell") and defect_entry.defect_supercell: return defect_entry.defect_supercell if ( hasattr(defect_entry, "sc_entry") and defect_entry.sc_entry and hasattr(defect_entry.sc_entry, "structure") and defect_entry.sc_entry.structure ): return defect_entry.sc_entry.structure return None def _get_unrelaxed_defect_structure(defect_entry: DefectEntry): if ( hasattr(defect_entry, "calculation_metadata") and defect_entry.calculation_metadata and "unrelaxed_defect_structure" in defect_entry.calculation_metadata ): return defect_entry.calculation_metadata["unrelaxed_defect_structure"] bulk_supercell = _get_bulk_supercell(defect_entry) if bulk_supercell is not None: from doped.analysis import defect_from_structures ( _defect, _defect_site, # _relaxed_ defect site in supercell (if substitution/interstitial) _defect_site_in_bulk, # bulk site for vacancies/substitutions, relaxed defect site # w/interstitials _defect_site_index, _bulk_site_index, _guessed_initial_defect_structure, unrelaxed_defect_structure, _bulk_voronoi_node_dict, ) = defect_from_structures( bulk_supercell, _get_defect_supercell(defect_entry), return_all_info=True, ) return unrelaxed_defect_structure return None def _get_defect_supercell_bulk_site_coords(defect_entry: DefectEntry, relaxed=True): sc_defect_frac_coords = defect_entry.sc_defect_frac_coords site = None if not relaxed and hasattr(defect_entry, "calculation_metadata") and defect_entry.calculation_metadata: site = defect_entry.calculation_metadata.get("bulk_site") if sc_defect_frac_coords is None and site is None: site = _get_defect_supercell_site(defect_entry) if site is not None: sc_defect_frac_coords = site.frac_coords return sc_defect_frac_coords def _get_defect_supercell_site(defect_entry: DefectEntry): if hasattr(defect_entry, "defect_supercell_site") and defect_entry.defect_supercell_site: return defect_entry.defect_supercell_site if defect_entry.sc_defect_frac_coords is not None: return PeriodicSite( defect_entry.defect.site.species, defect_entry.sc_defect_frac_coords, _get_defect_supercell(defect_entry).lattice, ) return None