Mpr.summary.search(...) returns mpids that seem to be missing from mpr.thermo.get_ phase_ diagram _from_ chemsys(...)

Materials Project
1

Hello!

Hopefully I’m not missing something obvious, but for chemsys “K-La-Mg-Na-Nb-O” I’m able to get two structures (MPID(mp-2231300) and MPID(mp-2230339)) using the mpr.summary.search(…) , but these structures are not returned by mpr.thermo.get_phase_diagram_from_chemsys(…), regardless of which thermo_type I use. Does anyone else get the same issue? Is there something I’m doing wrong or an undocumented thermo_type that would need to be used to get these two structures? Don’t think I ever ran into this with the old MP api

Input:

with MPRester(os.environ[“MY_MP_API_NEW”]) as mpr:

docs = mpr.summary.search(chemsys="K-La-Mg-Na-Nb-O", fields=["material_id","chemsys"])
print([doc.material_id for doc in docs])

try:
    pd_testNew = mpr.thermo.get_phase_diagram_from_chemsys(chemsys="K-La-Mg-Na-Nb-O",thermo_type="GGA_GGA+U")
except Exception as e:
    print(e)
    
try:
    pd_testNew = mpr.thermo.get_phase_diagram_from_chemsys(chemsys="K-La-Mg-Na-Nb-O",thermo_type="GGA_GGA+U_R2SCAN")
except Exception as e:
    print(e)
    
try:
    pd_testNew = mpr.thermo.get_phase_diagram_from_chemsys(chemsys="K-La-Mg-Na-Nb-O",thermo_type="R2SCAN")
except Exception as e:
    print(e)

try:
    pd_testNew = mpr.thermo.get_phase_diagram_from_chemsys(chemsys="K-La-Mg-Na-Nb-O",thermo_type="UNKNOWN")
except Exception as e:
    print(e)
    
try:
    pd_testNew = mpr.thermo.get_phase_diagram_from_chemsys(chemsys="K-La-Mg-Na-Nb-O")
except Exception as e:
    print(e)

Output:

[MPID(mp-2231300), MPID(mp-2230339)]
REST query returned with error status code 404 on URL https://api.materialsproject.org/materials/thermo/phase_diagram/K-La-Mg-Na-Nb-O_GGA_GGA+U/?_fields=phase_diagram with message:
Item with phase_diagram_id = K-La-Mg-Na-Nb-O_GGA_GGA+U not found
REST query returned with error status code 404 on URL https://api.materialsproject.org/materials/thermo/phase_diagram/K-La-Mg-Na-Nb-O_GGA_GGA+U_R2SCAN/?_fields=phase_diagram with message:
Item with phase_diagram_id = K-La-Mg-Na-Nb-O_GGA_GGA+U_R2SCAN not found
REST query returned with error status code 404 on URL https://api.materialsproject.org/materials/thermo/phase_diagram/K-La-Mg-Na-Nb-O_R2SCAN/?_fields=phase_diagram with message:
Item with phase_diagram_id = K-La-Mg-Na-Nb-O_R2SCAN not found
REST query returned with error status code 404 on URL https://api.materialsproject.org/materials/thermo/phase_diagram/K-La-Mg-Na-Nb-O_UNKNOWN/?_fields=phase_diagram with message:
Item with phase_diagram_id = K-La-Mg-Na-Nb-O_UNKNOWN not found
ThermoRester.get_phase_diagram_from_chemsys() missing 1 required positional argument: ‘thermo_type’

2

We currently don’t store the pre-computed phase diagram for chemical systems with elements > 5. This is changing in the next release, and all phase diagrams should readily be available via the API. For now, you will have to construct it locally. See Phase Diagrams (PDs) - Materials Project Documentation.

– Jason

3

Great thanks for the clarification