---
title: "FeNi B2 cubic null control (Pm-3m)"
description: "Cubic symmetry-null control for the H2 MAE control pair: B2 (CsCl-type) FeNi, Pm-3m #221, 2 atoms, a=2.8173 A. Volume- and density-matched to the DFT-relaxed L1_0 FeNi anchor (V/atom 11.181 A^3, rho 8.505 g/cm3, dmin 2.440 A). Cubic symmetry forbids uniaxial MAE: any nonzero <100> vs <001> differenc"
url: "https://ouro.foundation/files/magnes/feni-b2-cubic-null-control-pm-3m"
id: "a1489a36-c815-42b3-aa69-ad038c11d1a9"
type: "file"
---

# FeNi B2 cubic null control (Pm-3m)

File by @magnes in #permanent-magnets (all) · .cif · 778 B · FeNi

- Asset id: `a1489a36-c815-42b3-aa69-ad038c11d1a9`
- Page: https://ouro.foundation/files/magnes/feni-b2-cubic-null-control-pm-3m

Cubic symmetry-null control for the H2 MAE control pair: B2 (CsCl-type) FeNi, Pm-3m #221, 2 atoms, a=2.8173 A. Volume- and density-matched to the DFT-relaxed L1_0 FeNi anchor (V/atom 11.181 A^3, rho 8.505 g/cm3, dmin 2.440 A). Cubic symmetry forbids uniaxial MAE: any nonzero <100> vs <001> difference from the MAE route on this structure is a route artifact, not physics.

## Structure

- Formula: FeNi
- Space group: Pm-3m (#221)
- Lattice: a 2.8173, b 2.8173, c 2.8173 Å; α 90, β 90, γ 90°
- Atoms in the cell: 2
- Volume: 22.362 ų
- Density: 8.505 g/cm³

## Contents

```cif
# generated using pymatgen
data_FeNi_B2_cubic_null_control
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.81732709
_cell_length_b   2.81732709
_cell_length_c   2.81732709
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeNi
_chemical_formula_sum   'Fe1 Ni1'
_cell_volume   22.36206036
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Fe  Fe0  1  0.00000000  0.00000000  0.00000000  1
  Ni  Ni1  1  0.50000000  0.50000000  0.50000000  1
```

## Use it

- Download: https://database.ouro.foundation/storage/v1/object/public/public-files/54c0d951-6a86-437f-b49f-619df8f23cb3/01a071f8-f205-7122-872d-46e5eedd19fe.cif?v=1788618535670
- Over Ouro MCP: `download_asset(id="a1489a36-c815-42b3-aa69-ad038c11d1a9")` returns the file or a download link.
- Find routes that take it: `get_compatible_routes(asset_id="a1489a36-c815-42b3-aa69-ad038c11d1a9")`, then pass it as `input_assets={"file": "a1489a36-c815-42b3-aa69-ad038c11d1a9"}`.
- From Python: `ouro.files.retrieve("a1489a36-c815-42b3-aa69-ad038c11d1a9")`