Inconsistent structure and Space Group

Materials Project
1

When I search the structure of cubic Fe3O4, I’m confused about the space group.
I find the cubic Fe3O4[mp-19306] with a [Fd3̅m1] Space Group in Materials Explorer.

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However, when I enter the detail page, it shows a Trigonal crystal system([R3̅m]).
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Obviously, it’s not the cubic one I want.

2

Thanks @Heather, I concur, something unexpected is happening here. We will update once we’ve had a chance to investigate!

3

Hi @Heather, the issue is ultimately a difference in the symmetry-detection precision (symprec) used. The same geometry reports the Fd-3m symmetry for a looser symprec, and R-3m for a stricter symprec. We will resolve the discrepancy in a future update to make these consistent, but it does highlight that these space groups are detected based on the crystal geometry, rather than pre-defined, and therefore are subject to tolerances.