---
title: "FePt MAE accuracy: TB2J band window vs self-consistent SOC"
description: "L1₀ FePt magnetocrystalline anisotropy (meV/f.u.) from Ouro DFT (ABACUS LCAO, PBE, DZP, 100 Ry). The 2-atom cell (8×8×6) and a 2×2×2 supercell (4×4×3, an exactly equivalent k-mesh) are compared under different TB2J band windows and contour densities, a direct-diagonalisation variant, and a self-cons"
url: "https://ouro.foundation/datasets/mmoderwell/fept-mae-accuracy-tb2j-band-window-vs-self-consistent-soc"
id: "01a0ef71-1b6d-7483-ac89-075c84fef747"
type: "dataset"
---

# FePt MAE accuracy: TB2J band window vs self-consistent SOC

Dataset by @mmoderwell in #permanent-magnets (all) · 12 rows · 9 columns

- Asset id: `01a0ef71-1b6d-7483-ac89-075c84fef747`
- Page: https://ouro.foundation/datasets/mmoderwell/fept-mae-accuracy-tb2j-band-window-vs-self-consistent-soc

L1₀ FePt magnetocrystalline anisotropy (meV/f.u.) from Ouro DFT (ABACUS LCAO, PBE, DZP, 100 Ry). The 2-atom cell (8×8×6) and a 2×2×2 supercell (4×4×3, an exactly equivalent k-mesh) are compared under different TB2J band windows and contour densities, a direct-diagonalisation variant, and a self-consistent SOC total-energy reference. TB2J's former 5.1 eV band cut made the result depend on the cell; keeping all bands matches the reference to within 5 µeV. Unrelaxed fixture lattice (a = 2.73 Å, c = 3.71 Å).

## Columns

| Column | Type | Notes |
| --- | --- | --- |
| band_window | text |  |
| bands_kept_per_fu | double precision |  |
| cell | text |  |
| contour_points | double precision |  |
| highest_band_kept_ev_above_ef | double precision |  |
| id | uuid | primary key |
| kmesh | text |  |
| mae_mev_per_fu | double precision |  |
| method | text |  |

## First 5 rows

| band_window | bands_kept_per_fu | cell | contour_points | highest_band_kept_ev_above_ef | id | kmesh | mae_mev_per_fu | method |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| all | 92 | FePt 2x2x2 (16 atoms) | 100 | 917.1 | 01a0ef71-1d20-700c-9b05-aefcb3d22704 | 4x4x3 | 2.8598 | TB2J second order, all bands (production from v61) |
| all |  | FePt 2-atom |  |  | 01a0ef71-1d20-71c2-a25c-c773772ef7fb | 8x8x6 | 3.548 | Direct diagonalisation with SOC along each axis (TB2J smear… |
| all |  | FePt 2-atom | 100 |  | 01a0ef71-1d20-71e6-95a0-c453862d7eb6 | 8x8x6 | 2.8704 | Deployed route (v61 code, service.run_property) |
| all | 92 | FePt 2-atom | 100 | 917.1 | 01a0ef71-1d20-7213-8e0c-fa80126b2e64 | 8x8x6 | 2.8598 | TB2J second order, all bands (production from v61) |
| 5.1 eV cut | 25 | FePt 2-atom | 200 | 18.3 | 01a0ef71-1d20-72a9-aa94-28047b642338 | 8x8x6 | 3.1482 | TB2J second order, 5.1 eV band cut |

## Query it

Read-only SQL, with `{{table}}` standing for this dataset's table.

From an agent connected to Ouro MCP:

```
query_dataset(dataset_id="01a0ef71-1b6d-7483-ac89-075c84fef747", sql="SELECT * FROM {{table}} LIMIT 20")
```

From Python:

```python
df = ouro.datasets.query("01a0ef71-1b6d-7483-ac89-075c84fef747", "SELECT * FROM {{table}} LIMIT 20")
```