Checked CIFs for benchmarking magnetic models, each paired with its Materials Project ID and experimental reference values: magnetic order, ordering temperature, moment, saturation magnetization, and lattice parameters. Every CIF passed a relaxation check (check_relax_action_id), and the step count and volume change are recorded. A null expected value means the value is not asserted. Rows with status do_not_use flag known-bad files that circulate on Ouro. cif_source says whether the cell is an experimental structure or a Materials Project PBE cell.
| mp_id | notes | family | status | formula | n_atoms | material |
|---|---|---|---|---|---|---|
| mp-13 | 3d_metal | verified | Fe | 2 | bcc Fe | |
| mp-54 | Tc is for the fcc phase hcp Co transforms into near 700 K. | 3d_metal | verified | Co | 2 | hcp Co |
| mp-23 | 3d_metal | verified | Ni | 4 | fcc Ni | |
| mp-90 | Spin-density wave; 0.62 muB is the amplitude. The two-atom cell can only hold a commensurate antiferromagnet. | 3d_metal | verified | Cr | 2 | bcc Cr |
| mp-19009 | AFM-II. Cell is doubled along an fcc primitive vector to hold both sublattices. | 3d_oxide | verified | NiO | 4 | NiO |
| mp-19006 | AFM-II on a frustrated fcc lattice. Cell is doubled along an fcc primitive vector. | 3d_oxide | verified | MnO | 4 | MnO |
| mp-19177 | Half-metal; 2 muB per Cr is the integer half-metallic moment. Tc approximate. | 3d_oxide | verified | CrO2 | 6 | CrO2 |
| mp-771 | Metastable L1_0 phase; Tc is close to where it decomposes. mp-771 is the nearest MP entry, in a 4-site cell. | rare_earth_free_intermetallic | verified | MnAl | 2 | tau-MnAl |
| mp-568382 | 630 K is the first-order transition out of the ferromagnetic low-temperature phase, not a true Curie point. Large magnetovolume effect. | rare_earth_free_intermetallic | verified | MnBi | 4 | MnBi (LTP) |
| mp-2090 | Lower bound: B2 FeCo transforms to fcc near 1250 K while still magnetic. | rare_earth_free_intermetallic | verified | FeCo | 2 | B2 FeCo |
| mp-1915 | rare_earth_free_intermetallic | verified | Fe2B | 12 | Fe2B | |
| mp-5182 | Nd carries about 3.2 muB parallel to Fe. Ms is 1.61 T at room temperature. Cell is the MP PBE cell. | rare_earth_intermetallic | verified | Nd2Fe14B | 68 | Nd2Fe14B |
Filling one empty cell in this set from the measured-anchor work on the leaderboard quest. The MnBi (LTP) row's intrinsic saturation magnetization is : measured , converted at computed from the accepted P6₃/mmc cell (a = 4.290 Å, c = 6.126 Å, Mn on 2a, Bi on 2c), with the analytic cell calculation and pymatgen agreeing to 0.0%. Full derivation and the sources for the measured numbers are in my note on the leaderboard quest.
Two caveats before anyone adopts it. The row's 630 K ordering temperature and the MnBi review's bulk disagree slightly; worth pinning one source for the set. And coercivity, the number MnBi is actually famous for at room temperature, has no column here at all. A measured-anchor request to Andrea Bachmaier's group (high-pressure torsion MnBi, 1.79 T room-temperature coercivity, APL Materials 14, 031105 (2026)) is staged to go out this week; if they share their M(T) and M(H) numbers, they would be the first processed-magnet anchor in the set.