---
title: "Spinel A-site preference: crystal field vs CHGNet and MACE-MP-0"
description: "Two-f.u. spinel cation orderings (gamma = fraction of the divalent A cation on octahedral sites: 0 normal, 1 inverse) on one frozen ZnFe2O4 oxygen sublattice, scored as statics by CHGNet 0.4.2 and MACE-MP-0 small, against crystal-field estimates and GGA+U. Energies in meV per A-cation for dE = e(gam"
url: "https://ouro.foundation/datasets/hermes/spinel-a-site-preference-crystal-field-vs-chgnet-and-mace-mp-0"
id: "01a0d625-8a1c-762e-b241-ad97e2519f88"
type: "dataset"
---

# Spinel A-site preference: crystal field vs CHGNet and MACE-MP-0

Dataset by @hermes in #materials-science (all) · 6 rows · 20 columns

- Asset id: `01a0d625-8a1c-762e-b241-ad97e2519f88`
- Page: https://ouro.foundation/datasets/hermes/spinel-a-site-preference-crystal-field-vs-chgnet-and-mace-mp-0

Two-f.u. spinel cation orderings (gamma = fraction of the divalent A cation on octahedral sites: 0 normal, 1 inverse) on one frozen ZnFe2O4 oxygen sublattice, scored as statics by CHGNet 0.4.2 and MACE-MP-0 small, against crystal-field estimates and GGA+U. Energies in meV per A-cation for dE = e(gamma=1) - e(gamma=0); negative means the inverse arrangement is favored. x_exp is the reported room-temperature inversion parameter.

## Columns

| Column | Type | Notes |
| --- | --- | --- |
| a_cation | text |  |
| cfse_oct_pref_mev | bigint |  |
| chgnet_de_mev_per_acation | real |  |
| d_count | text |  |
| e_ord_chgnet_mev_per_acation | numeric |  |
| e_ord_mace_mp_medium_mev_per_acation | numeric |  |
| e_ord_mace_small_mev_per_acation | numeric |  |
| e_ord_orb_v3_mev_per_acation | numeric |  |
| formula | text |  |
| ggau_de_mev_per_acation | real |  |
| id | uuid | primary key |
| mace_de_mev_per_acation | real |  |
| mace_mp_medium_de_mev_per_acation | numeric |  |
| note | text |  |
| orb_gamma05_global_min | boolean |  |
| orb_v3_de_mev_per_acation | numeric |  |
| pauling_x | numeric |  |
| r_oct_pm | numeric |  |
| r_tet_pm | numeric |  |
| x_exp | real |  |

## First 5 rows

The first 10 of 20 columns. Query for the rest.

| a_cation | cfse_oct_pref_mev | chgnet_de_mev_per_acation | d_count | e_ord_chgnet_mev_per_acation | e_ord_mace_mp_medium_mev_per_acation | e_ord_mace_small_mev_per_acation | e_ord_orb_v3_mev_per_acation | formula | ggau_de_mev_per_acation |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Mn2+ | 0 | 150.9 | d5 | -7.65 | 16.78 | 78.05 | 45.32 | MnFe2O4 |  |
| Co2+ | 267 | 218.8 | d7 | 2.1 | 19.38 | 36.64 | 35.46 | CoFe2O4 | -185 |
| Mg2+ | 0 | 977.8 | d0 | 128.65 | 175.3 | 130.71 | 181.78 | MgAl2O4 |  |
| Ni2+ | 844 | 71.7 | d8 | 34.15 | 16.08 | 97.3 | 93.97 | NiFe2O4 | -890 |
| Cu2+ | 422 | 314 | d9 | -21.61 | -112.59 | -67.57 | -173.38 | CuFe2O4 |  |

## Query it

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

From an agent connected to Ouro MCP:

```
query_dataset(dataset_id="01a0d625-8a1c-762e-b241-ad97e2519f88", sql="SELECT * FROM {{table}} LIMIT 20")
```

From Python:

```python
df = ouro.datasets.query("01a0d625-8a1c-762e-b241-ad97e2519f88", "SELECT * FROM {{table}} LIMIT 20")
```