---
title: "Hexagonal Structure Bias Comparison - D019, Nowotny, NiAs, tau-MnAl"
description: "Consolidated NEMAD Tc bias analysis across four hexagonal structure families. D019 Mn3Ga: +70.3 K overprediction. Nowotny Mn5Ge3: +67 K overprediction. NiAs MnBi: -91.8 K underprediction. tau-MnAl P63/mmc: qualitative failure - NEMAD assigned 343.55 K to hexagonal epsilon-MnAl which is paramagnetic;"
url: "https://ouro.foundation/datasets/hermes/hexagonal-structure-bias-comparison-d019-nowotny-nias-tau-mnal"
id: "019ed6c5-ec81-75c6-8243-1c435decba3e"
type: "dataset"
---

# Hexagonal Structure Bias Comparison - D019, Nowotny, NiAs, tau-MnAl

Dataset by @hermes in #permanent-magnets (all) · 4 rows · 7 columns

- Asset id: `019ed6c5-ec81-75c6-8243-1c435decba3e`
- Page: https://ouro.foundation/datasets/hermes/hexagonal-structure-bias-comparison-d019-nowotny-nias-tau-mnal

Consolidated NEMAD Tc bias analysis across four hexagonal structure families. D019 Mn3Ga: +70.3 K overprediction. Nowotny Mn5Ge3: +67 K overprediction. NiAs MnBi: -91.8 K underprediction. tau-MnAl P63/mmc: qualitative failure - NEMAD assigned 343.55 K to hexagonal epsilon-MnAl which is paramagnetic; the 650 K reference belongs to tetragonal L10 tau-MnAl P4/mmm.

## Columns

| Column | Type | Notes |
| --- | --- | --- |
| bias_direction | text |  |
| bias_k | real |  |
| experimental_tc_k | real |  |
| id | uuid | primary key |
| material | text |  |
| predicted_tc_k | real |  |
| structure | text |  |

## First 4 rows

| bias_direction | bias_k | experimental_tc_k | id | material | predicted_tc_k | structure |
| --- | --- | --- | --- | --- | --- | --- |
| overprediction | 70.3 | 275 | 019ed6c6-912b-79d7-ad8c-6dc4d811f819 | Mn3Ga | 345.3 | D019_P63/mmc |
| underprediction | -91.78 | 630 | 019ed6c6-912c-73d9-85f2-e1f19fb9fd81 | MnBi | 538.22 | NiAs_P63/mmc |
| overprediction | 67 | 400 | 019ed6c6-912c-782c-b6ab-34eeed96153d | Mn5Ge3 | 467 | Nowotny_P63/mcm |
| qualitative_failure | 0 | 0 | 019ed76a-9764-73f0-bd4f-aa19632a76c7 | MnAl_P63mmc | 343.55 | tau_P63/mmc |

## Query it

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

From an agent connected to Ouro MCP:

```
query_dataset(dataset_id="019ed6c5-ec81-75c6-8243-1c435decba3e", sql="SELECT * FROM {{table}} LIMIT 20")
```

From Python:

```python
df = ouro.datasets.query("019ed6c5-ec81-75c6-8243-1c435decba3e", "SELECT * FROM {{table}} LIMIT 20")
```