jarvis.ai.descriptors.cfid

Classical Force-field Inspired Descriptors (CFID).

The CFID provide a complete set of chemo-structural descriptors able to differentiate between structural prototypes. Specifically, the combination of pairwise radial, nearest neighbor, bond-angle, dihedral-angle and core-charge distributions, together with hundreds of chemistry-related descriptors, plays an important role in predicting formation energies, bandgaps, static refractive indices, magnetic properties, and modulus of elasticity for 3D materials as well as exfoliation energies of two-dimensional (2D) layered materials.

The 1557 CFID are described in detail below:

Descriptor name	Array_index	Total number
Chemical (mean_chem)	0-437	438
Simulation cell-size (cell)	438-441	4
Radial charge (mean_chg)	442-819	378
Radial distribution function (rdf)	820-919	100
Angular distribution upto 1st nn cutoff (adfa)	920-1098	179
Angular distribution upto 2nd nn cutoff (adfb)	1099-1277	179
Dihedral distribution upto 1st nn cutoff (ddf)	1278-1456	179
Nearest neighbor distribution (nn)	1457-1556	100
Total		1557

Details of element based chemical descriptors are below:

Descriptor_name	Details
jv_enp	Energy per atom of an element from JARVIS-DFT
KV	Bulk modulus of an element from JARVIS-DFT
GV	Shear modulus of an element from JARVIS-DFT
C-m (m=0 to 35)	Elastic constants of element from JARVIS-DFT (total 36)
op_eg	OptB88vdW bandgap during SCF for an element
mop_eg	OptB88vdW bandgap during linear optics for element
voro_coord	Voronoi coordination number of an elemental-crystal structure
ndunfilled	Number of unfilled d-orbitals
ndvalence	Number of valence d-orbitals
nsunfilled	Number of unfilled s-orbitals
nsunfilled	Number of valence s-orbitals
npunfilled	Number of unfilled p-orbitals
npvalence	Number of valence p-orbitals
nfunfilled	Number of unfilled f-orbitals
nfvalence	Number of valence f-orbitals
first_ion	First ionization energy of an element
oq_bg	OQMD bandgap for an element
elec_aff	Electron affinity
vol_pa	Volume per atom of an element
hfus	Heat of fusion of an element
oq_enp	OQMD energy per atom
Polariz	Polarizability
Z	Atomic number
X	Electronegativity
row	Row number in the periodic table
column	Column number in the periodic table
max_oxid_s	Maximum oxidation state
min_oxid_s	Minimum oxidation state
block	s,p,d,f block assigned to 0,1,2,3 blocks
is_alkali	Is it alkali element 0/1
is_alkaline	Is it alkaline element 0/1
is_metalloid	Is it metalloid element 0/1
is_noble_gas	Is it noble gas element 0/1
is_transition_metal	Is it transition element 0/1
is_metalloid	Is it metalloid element 0/1
is_halogen	Is it halogen element 0/1
is_lanthanoid	Is it lanthanoid element 0/1
is_actinoid	Is it actinoid element 0/1
atom_mass	Atomic mass
atom_rad	Atomic radii
therm_cond	Thermal conductivity
mol_vol	Molar volume
bp	Boiling point
mp	Melting point
avg_ion_rad	Average ionic radii
polzbl	Polarizability
e1	Static dielectric function in x-direction from JARVIS-DFT using OptB88vdW functional
e2	Static dielectric function in y-direction from JARVIS-DFT using OptB88vdW functional
e3	Static dielectric function in z-direction from JARVIS-DFT using OptB88vdW functional
me1	Static dielectric function in x-direction from JARVIS-DFT using TB-mBJ potential
me2	Static dielectric function in y-direction from JARVIS-DFT using TB-mBJ potential
me3	Static dielectric function in z-direction from JARVIS-DFT using TB-mBJ potential

Addition (‘add’), multiplications (‘mult’), subtraction (‘subs’) and quotient (‘divi’) of hfus, polzbl, first_ion_en, mol_vol, bp,mp, mol_vol, mol_vol, therm_cond and voro_coord were performed to give additional chemical descriptors.

Details of simulation cell-size based descriptors are below:

Descriptor_name	Details
cell_0	Volume per atom of the cell
cell_1	Logarithm of volume per atom of the cell
cell_2	Packing fraction
cell_3	Density

Find details in: https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.2.083801

Module Contents

Classes

CFID	Convert Atoms class into 1557 descriptors.

Functions

get_chem_only_descriptors([formula, extra, mean_only, ...])	Get jarvis_cfid or magpie descriptors for each formula.
feat_names()	Names of the 1557 descriptors.

jarvis.ai.descriptors.cfid.get_chem_only_descriptors(formula='Al2O3', extra=[], mean_only=False, max_only=False, min_only=False, source='cfid')

Get jarvis_cfid or magpie descriptors for each formula.

class jarvis.ai.descriptors.cfid.CFID(atoms)

Bases: object

Convert Atoms class into 1557 descriptors.

get_comp_descp(jcell=True, jmean_chem=True, jmean_chg=True, jrdf=False, jrdf_adf=True, print_names=False)

Get chemo-structural CFID decriptors.

Args:

jcell: whether to use cell-size descriptors

jmean_chem: whether to use average chemical descriptors

jmean_chg: whether to use average charge distribution descriptors

jmean_rdf: whether to use radial distribution descriptors

jrdf_adf: whether to use radial and angle distribution descriptors

print_names: whether to print names of descriptors

Returns:

cat: catenated final descriptors

jarvis.ai.descriptors.cfid.feat_names()

Names of the 1557 descriptors.