5. Parameter List

5.1. Search conditions (properties)

Table Search criteria summarizes condition terms available in the properties section.

getcif uses the mp-api library provided by Materials Project as a client for accessing the database via Materials Project API. The condition terms correspond to the parameters for the materials.summary.search method of MPRester class in mp-api. (The content of the table is taken and reformatted from the comments of the source file in mpi-api.)

The types of the parameter values denote as follows:

• str: a string

• List[str]: a list of strings

• str | List[str]: a string or a list of strings

• int: an integer

• bool: a boolean value (true or false)

• Tuple[float,float]: a pair of two floating point numbers (as a list)

• Tuple[int,int]: a pair of two integers (as a list)

• CrystalSystem: a string representing the crystal system, one of the following: Triclinic, Monoclinic, Orthorhombic, Tetragonal, Trigonal, Hexagonal, Cubic

• List[HasProps]: a list of strings representing the properties defined in emmet.core.summary. The available terms include:

  absorption, bandstructure, charge_density, chemenv, dielectric, dos, elasticity, electronic_structure, eos, grain_boundaries, insertion_electrodes, magnetism, materials, oxi_states, phonon, piezoelectric, provenance, substrates, surface_properties, thermo, xas

• Ordering: a string representing the magnetic ordering, one of the following: FM, AFM, FiM, NM

A list of the values is described in an indented style or in a comma-separated bracketted style in YAML notation. It is also available that it is described as a space-separated list.

A Tuple is used to denote a range of values by min and max. It is described by a list of two numbers, as well as by a space-separated list as min max. The following notation is also available:

< max

less than or equal to max

> min

more than or equal to min

min ~ max

between min and max

Table 5.1 Search criteria

Keyword	Type	Description
band_gap	Tuple[float,float]	Minimum and maximum band gap in eV to consider.
chemsys	str | List[str]	A chemical system, list of chemical systems (e.g., Li-Fe-O, Si-*, [Si-O, Li-Fe-P]), or single formula (e.g., Fe2O3, Si*).
crystal_system	CrystalSystem	Crystal system of material.
density	Tuple[float,float]	Minimum and maximum density to consider.
deprecated	bool	Whether the material is tagged as deprecated.
e_electronic	Tuple[float,float]	Minimum and maximum electronic dielectric constant to consider.
e_ionic	Tuple[float,float]	Minimum and maximum ionic dielectric constant to consider.
e_total	Tuple[float,float]	Minimum and maximum total dielectric constant to consider.
efermi	Tuple[float,float]	Minimum and maximum fermi energy in eV to consider.
elastic_anisotropy	Tuple[float,float]	Minimum and maximum value to consider for the elastic anisotropy.
elements	List[str]	A list of elements.
energy_above_hull	Tuple[int,int]	Minimum and maximum energy above the hull in eV/atom to consider.
equilibrium_reaction_energy	Tuple[float,float]	Minimum and maximum equilibrium reaction energy in eV/atom to consider.
exclude_elements	List[str]	List of elements to exclude.
formation_energy	Tuple[int,int]	Minimum and maximum formation energy in eV/atom to consider.
formula	str | List[str]	A formula including anonymized formula or wild cards (e.g., Fe2O3, ABO3, Si*). A list of chemical formulas can also be passed (e.g., [Fe2O3, ABO3]).
g_reuss	Tuple[float,float]	Minimum and maximum value in GPa to consider for the Reuss average of the shear modulus.
g_voigt	Tuple[float,float]	Minimum and maximum value in GPa to consider for the Voigt average of the shear modulus.
g_vrh	Tuple[float,float]	Minimum and maximum value in GPa to consider for the Voigt-Reuss-Hill average of the shear modulus.
has_props	List[HasProps]	The calculated properties available for the material.
has_reconstructed	bool	Whether the entry has any reconstructed surfaces.
is_gap_direct	bool	Whether the material has a direct band gap.
is_metal	bool	Whether the material is considered a metal.
is_stable	bool	Whether the material lies on the convex energy hull.
k_reuss	Tuple[float,float]	Minimum and maximum value in GPa to consider for the Reuss average of the bulk modulus.
k_voigt	Tuple[float,float]	Minimum and maximum value in GPa to consider for the Voigt average of the bulk modulus.
k_vrh	Tuple[float,float]	Minimum and maximum value in GPa to consider for the Voigt-Reuss-Hill average of the bulk modulus.
magnetic_ordering	Ordering	Magnetic ordering of the material.
material_ids	List[str]	List of Materials Project IDs to return data for.
n	Tuple[float,float]	Minimum and maximum refractive index to consider.
num_elements	Tuple[int,int]	Minimum and maximum number of elements to consider.
num_sites	Tuple[int,int]	Minimum and maximum number of sites to consider.
num_magnetic_sites	Tuple[int,int]	Minimum and maximum number of magnetic sites to consider.
num_unique_magnetic_sites	Tuple[int,int]	Minimum and maximum number of unique magnetic sites to consider.
piezoelectric_modulus	Tuple[float,float]	Minimum and maximum piezoelectric modulus to consider.
poisson_ratio	Tuple[float,float]	Minimum and maximum value to consider for Poisson’s ratio.
possible_species	List[str]	List of element symbols appended with oxidation states. (e.g. Cr2+,O2-)
shape_factor	Tuple[float,float]	Minimum and maximum shape factor values to consider.
spacegroup_number	int	Space group number of material.
spacegroup_symbol	str	Space group symbol of the material in international short symbol notation.
surface_energy_anisotropy	Tuple[float,float]	Minimum and maximum surface energy anisotropy values to consider.
theoretical	bool	Whether the material is theoretical.
total_energy	Tuple[int,int]	Minimum and maximum corrected total energy in eV/atom to consider.
total_magnetization	Tuple[float,float]	Minimum and maximum total magnetization values to consider.
total_magnetization_normalized_formula_units	Tuple[float,float]	Minimum and maximum total magnetization values normalized by formula units to consider.
total_magnetization_normalized_vol	Tuple[float,float]	Minimum and maximum total magnetization values normalized by volume to consider.
uncorrected_energy	Tuple[int,int]	Minimum and maximum uncorrected total energy in eV/atom to consider.
volume	Tuple[float,float]	Minimum and maximum volume to consider.
weighted_surface_energy	Tuple[float,float]	Minimum and maximum weighted surface energy in J/\(m^2\) to consider.
weighted_work_function	Tuple[float,float]	Minimum and maximum weighted work function in eV to consider.

5.2. Data to retrive (fields)

The items available for the fields section for retrieving from the database are listed below.

band_gap
bandstructure
builder_meta
bulk_modulus
cbm
chemsys
composition
composition_reduced
database_IDs
decomposes_to
density
density_atomic
deprecated
deprecation_reasons
dos
dos_energy_down
dos_energy_up
e_electronic
e_ij_max
e_ionic
e_total
efermi
elements
energy_above_hull
energy_per_atom
equilibrium_reaction_energy_per_atom
es_source_calc_id
formation_energy_per_atom
formula_anonymous
formula_pretty
grain_boundaries
has_props
has_reconstructed
homogeneous_poisson
is_gap_direct
is_magnetic
is_metal
is_stable
last_updated
material_id
n
nelements
nsites
num_magnetic_sites
num_unique_magnetic_sites
ordering
origins
possible_species
property_name
shape_factor
shear_modulus
structure
surface_anisotropy
symmetry
task_ids
theoretical
total_magnetization
total_magnetization_normalized_formula_units
total_magnetization_normalized_vol
types_of_magnetic_species
uncorrected_energy_per_atom
universal_anisotropy
vbm
volume
warnings
weighted_surface_energy
weighted_surface_energy_EV_PER_ANG2
weighted_work_function
xas