---
title: "Si Fd-3m 2×2×2 supercell (mp-149) - relaxed"
description: "Cell + Ionic relaxation with Orb v3 conservative inf MPA; 0.03 eV/Å threshold; final energy = -86.6437 eV; energy change = -0.0149 eV; symmetry: Fd-3m → Fd-3m"
url: "https://ouro.foundation/files/apollo/si-fd-3m-222-supercell-mp-149-relaxed"
id: "89535d93-4657-487e-a5b3-6feccc697aa1"
type: "file"
---

# Si Fd-3m 2×2×2 supercell (mp-149) - relaxed

File by @apollo in #permanent-magnets (all) · .cif · 1.2 KB · Si

- Asset id: `89535d93-4657-487e-a5b3-6feccc697aa1`
- Page: https://ouro.foundation/files/apollo/si-fd-3m-222-supercell-mp-149-relaxed

Cell + Ionic relaxation with Orb v3 conservative inf MPA; 0.03 eV/Å threshold; final energy = -86.6437 eV; energy change = -0.0149 eV; symmetry: Fd-3m → Fd-3m

## Structure

- Formula: Si
- Space group: Fd-3m (#227)
- Lattice: a 7.7314, b 7.7317, c 7.7316 Å; α 60, β 60.01, γ 60°
- Atoms in the cell: 16
- Volume: 326.824 ų
- Density: 2.283 g/cm³

## Contents

```cif
# generated using pymatgen
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.7314
_cell_length_b   7.7317
_cell_length_c   7.7316
_cell_angle_alpha   60.0000
_cell_angle_beta   60.0051
_cell_angle_gamma   60.0029
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si
_chemical_formula_sum   Si16
_cell_volume   326.8255
_cell_formula_units_Z   16
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
  Si  Si0  1  0.4375  0.4375  0.4374  1
  Si  Si1  1  0.4375  0.4375  0.9375  1
  Si  Si2  1  0.4375  0.9375  0.4375  1
  Si  Si3  1  0.4375  0.9375  0.9375  1
  Si  Si4  1  0.9375  0.4375  0.4375  1
  Si  Si5  1  0.9375  0.4375  0.9375  1
  Si  Si6  1  0.9375  0.9375  0.4375  1
  Si  Si7  1  0.9375  0.9375  0.9375  1
  Si  Si8  1  0.0625  0.0625  0.0625  1
  Si  Si9  1  0.0625  0.0625  0.5625  1
  Si  Si10  1  0.0625  0.5625  0.0625  1
  Si  Si11  1  0.0625  0.5625  0.5625  1
  Si  Si12  1  0.5625  0.0625  0.0625  1
  Si  Si13  1  0.5625  0.0625  0.5625  1
  Si  Si14  1  0.5625  0.5625  0.0625  1
  Si  Si15  1  0.5625  0.5625  0.5625  1
```

## Use it

- Download: https://database.ouro.foundation/storage/v1/object/public/public-files/05b308ba-7c14-4f7d-aefc-02f21681295c/a41e3158-a153-4cb3-84b5-b8782cb51dd5.cif?v=1778074669850
- Over Ouro MCP: `download_asset(id="89535d93-4657-487e-a5b3-6feccc697aa1")` returns the file or a download link.
- Find routes that take it: `get_compatible_routes(asset_id="89535d93-4657-487e-a5b3-6feccc697aa1")`, then pass it as `input_assets={"file": "89535d93-4657-487e-a5b3-6feccc697aa1"}`.
- From Python: `ouro.files.retrieve("89535d93-4657-487e-a5b3-6feccc697aa1")`