The MaterialsWeb API is built on the Materials API (MAPI). The best way to access our database is through the MWRester class implemented in QuantumML as shown below.

Connecting to materialsweb
from quantumML.rest import MWRester
with MWRester() as mwr:


To refine the query results the following filters may be applied

Applying filters
from quantumML.rest importb> MWRester
with MWRester() as mwr:
    mwr.get_calculation(band_gap_range=[1,1.5], formation_energy_range=[124,150])

This will store the querry as a list of Json response that can be accessed by mwr.results. A single Json response is shown below:

Json response

{'url': '',
 'configuration': None,
 'dimension': 2,
 'label': 'mp-700',
 'path': '/var/www/materialsweb/static/database/mp-700',
 'natoms': 4,
 'settings': "{'potentials': [{'name': 'Ge_d', 'xc': 'PBE', 'us': False, 'paw': True}, {'name': 'Se', 'xc': 'PBE', 'us': False, 'paw': True}], 'nbands': 28, 'prec': 'accura', 'istart': 0, 'icharg': 2, 'ispin': 2, 'encut': 500.0, 'nelm': 60, 'nelmin': 2, 'ediff': 1e-06, 'lreal': True, 'nsw': 50, 'ibrion': 2, 'isif': 3, 'potim': 0.5, 'pstress': 0.0, 'ismear': 1, 'sigma': 0.1, 'algo': 'fast', 'lwave': True, 'lcharg': True, 'lvtot': False, 'lorbit': 0, 'ldipol': False, 'idipol': 0, 'epsilon': 1.0}",
 'energy': -10.4702046,
 'energy_pa': -2.61755115,
 'magmom': -0.0001349,
 'magmom_pa': -3.3725e-05,
 'band_gap': 1.2107,
 'is_direct': False,
 'irreducible_kpoints': 42.0,
 'formation_energy': 133.0,
 'attempt': 0,
 'nsteps': 32,
 'converged': True,
 'runtime': None,
 'entry': '',
 'composition': '',
 'input': '',
 'output': '',
 'dos': '',
 'element_set': ['',

The content of each querry element can be accessed through pythons dictionary syntax as shown below:

Printing results
for results in mwr.results:
    print(results['composition'] + '\t Bandgap = ' + str(results['band_gap'])
Pd120S2			 BandGap = 1.1746
Ge120Se1		 BandGap = 1.2107
Pd120Se2		 BandGap = 1.3964
I220Pt1			 BandGap = 1.4215
I220Pd1			 BandGap = 1.1512
Br320Cr1		 BandGap = 1.4714
Cr120H120O2		 BandGap = 1.0072
Mo120O3			 BandGap = 1.1381

Write files

currently there are two methods to write the files from a query. The get_calculation method will store all the entries as a list. As a result one can write all of the files from a querry to a directory using the write_all method or write the files of a specific entry using the write method:

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