Hi MP manager,
I met a problem when I was trying to get the conventional cell from materials project by using API (ID: mp-37). I have two ways to get conventional cell and they return me different structures by using the same mp-id.
First way:
m = MPRester(“xxx”)
entry = m.get_entry_by_material_id(material_id=“mp-37”,
compatible_only=True,
inc_structure=True,
property_data=None,
conventional_unit_cell=True)
print(entry.structure)
Full Formula (Th2)
Reduced Formula: Th
abc : 2.822000 2.822000 4.411000
angles: 90.000000 90.000000 90.000000
Sites (2)
SP a b c
0 Th 0 0 0
1 Th 0.5 0.5 0.5
Second way:
m = MPRester(“xxx”)
Th = m.get_structure_by_material_id(“mp-37”, final=True, conventional_unit_cell=True)
print(Th)
Full Formula (Th4)
Reduced Formula: Th
abc : 5.041217 5.041217 5.041217
angles: 90.000000 90.000000 90.000000
Sites (4)
SP a b c
0 Th 0 0 0
1 Th 0 0.5 0.5
2 Th 0.5 0 0.5
3 Th 0.5 0.5 0
The second way returns same structure by downloading from the MP website, which is the structure I expected. While by using the first way, the conventional structure I got is expected, not fcc.
Thank you for your concern!
Best,
Tina