aiida_cusp.utils.potcar module

Utility module implementing several methods for parsing and interacting with VASP potential files.

class aiida_cusp.utils.potcar.PotcarParser(path_to_potcar_file, name=None, functional=None)

Bases: object

Minimalistic parsing library for VASP POTCAR files.

Only tries to parse the basic potential identifiers from the file, i.e. the potential version and the associated element. Does not perform any checks on the validity of the parsed results but only raises if no match was retrieved at all.

Parameters:

• path_to_potcar_file (pathlib.Path) – path to a VASP POTCAR file

• name (str) – name of the potential (i.e. Li, Li_sv, …)

• functional (str) – functional of the potential, i.e. one of lda_us, lda, lda_52, lda_54, pbe, pbe_52, pbe_54, pw91 or pw91_us

apply_quirks()

Update invalid and erroneous parameters running the stored quirks

hash_contents()

Hash potential contents using secure hashing.

Calculates the hash based on the reduced instead of the full potential contents to avoid potentials being assumed as different if whitespaces differ.

Returns:

return sha256 hash for potential contents

Return type:

str

load_potential_contents()

Load POTCAR file contents.

Returns:

the contents of the potcar file

Return type:

str

load_reduced_contents()

Load POTCAR file contents and return a reduced version without consecutive whitespaces and occasionally occuring ‘^’ chars

Returns:

returns the reduced contents of the potcar file

Return type:

str

potential_element()

Extract the element stored with the potential

Returns:

string containing the element name

Return type:

str

Raises:

PotcarParserError – if regex returns with no match

potential_header()

Extract header section from potential contents

Returns:

string containing the potential header

Return type:

str

Raises:

PotcarParserError – if regex returns with no match

potential_title()

Extract the potential title (i.e. the first line of the file)

potential_version()

Extract creation date from the potential header

Returns:

integer representation of the potential creation date

Return type:

int

verify_parsed()

Check if the parsed contents do make sense.

class aiida_cusp.utils.potcar.PotcarPathParser(potcar_file_path)

Bases: object

Utility class for parsing POTCAR file paths.

Assumes a POTCAR file path of the form /path/[FUNCTIONAL]/[NAME]/POTCAR with [FUNCTIONAL] containing the archive name of the potential libraries as shipped by VASP, i.e. one of potuspp_lda, potpaw_lda, potpaw_lda.52, potpaw_lda.54, potpaw_pbe, potpaw_pbe.52, potpaw_pbe.54, potuspp_gga or potpaw_gga. Tries to determine the potential’s functional and name from the given path and raises an exception if this fails.

Parameters:

potcar_file_path (pathlib.Path) – file path pointing to a VASP pseudo-potential

Raises:

PotcarPathError – if the path does not point to a POTCAR file or if the path does not contain a valid archive name to identify the corresponding functional

parse_functional(path)

Parse the potential’s functional type from the given path.

Search the given path for functional identifiers corresponding to the archive names chosen by the pseudo-potential libraries shipped with VASP.

Parameters:

path (pathlib.Path) – file path pointing to a VASP pseudo-potential

Returns:

plugin internal functional identifier

Return type:

str

Raises:

PotcarPathError – if no valid functional identifier can be found in the given path.

parse_name(path)

Parse the unique functional name from the path.

Simply returns the name of the parent folder containing the POTCAR file.

Parameters:

path (pathlib.Path) – file path pointing to a VASP pseudo-potential

Returns:

the pseudo-potential’s unique name

Return type:

str

validate_path_is_potcar_file(path)

Check if the given path points to a file of type POTCAR .

Parameters:

path (pathlib.Path) – file path pointing to a VASP pseudo-potential

Raises:

PotcarPathError – if the parser cannot extract the functional from the path or if the path does not point to a potential