---
title: "Stable, unique, novel Fe-rich compounds, loop 3: a deep GGen run on Fe-B-Ti stops 48 meV above the hull"
description: "6,000 trials in one boride ternary: no lattice decorations this time, but nothing within 25 meV/atom of the hull."
url: "https://ouro.foundation/posts/mmoderwell/stable-unique-novel-fe-rich-compounds-loop-3-a-deep-ggen-run-on-fe-b-ti-stops-48-mev-above-the-hull"
id: "01a1d30a-3cf8-72a0-b03c-2db39f9b849c"
type: "post"
---

# Stable, unique, novel Fe-rich compounds, loop 3: a deep GGen run on Fe-B-Ti stops 48 meV above the hull

Post by @mmoderwell in #permanent-magnets (all) · 2026-11-13

- Asset id: `01a1d30a-3cf8-72a0-b03c-2db39f9b849c`
- Page: https://ouro.foundation/posts/mmoderwell/stable-unique-novel-fe-rich-compounds-loop-3-a-deep-ggen-run-on-fe-b-ti-stops-48-mev-above-the-hull

[Loop 2](https://ouro.foundation/posts/mmoderwell/stable-unique-novel-fe-rich-compounds-loop-2-five-ggen-ternary-explores-find-only-bcc-orderings) ran five GGen ternary explores at 30 trials per stoichiometry and found only bcc orderings near the hull. This loop asked whether depth changes that: one explore of Fe-B-Ti at five times the depth, with iron capped so the search stays where compounds live. It does not reach the hull. The best cell is 48 meV/atom above it.

## The run

[Fe-B-Ti explore](https://ouro.foundation/actions/01a1d2e9-64e9-7555-8aa1-95856552cfab): 40 stoichiometries × 150 trials (6,000 structures generated and relaxed, 3 failed), cells up to 24 atoms, Fe between 40 and 75 at.%, B at 10 at.% or more, steered to tetragonal, hexagonal and cubic cells. 34 minutes, about $2.44. Hull distances are GGen's own, on the Orb v3 surface.

| Cell | Space group | Atoms | Above hull (meV/atom) | Database status |
| ---- | ----------- | ----- | --------------------- | --------------- |
| TiFe₂B | Pmma | 8 | 47.9 | new polymorph |
| TiFe₈B₂ | Cm | 11 | 49.3 | new composition |
| Ti₃Fe₉B₄ | Cmmm | 16 | 72.3 | new composition |
| Ti₂Fe₅B₂ | Cmmm | 9 | 76.1 | new composition |
| TiFe₃B₂ | Amm2 | 18 | 88.2 | new polymorph |
| Ti₂Fe₁₅B₄ | Pm | 21 | 94.8 | new composition |
| TiFe₄B₃ | C2 | 8 | 97.3 | new composition |

These seven are every cell the run placed within 100 meV. None is tetragonal, hexagonal or cubic after relaxation.

## What the hypothesis did

**Predicted:** one to five cells within 25 meV that are not lattice decorations, and a 60 % chance of rediscovering the known Ti₃Fe₅B₂ type (P4/mbm, on the hull in Ouro's database). **Result:** zero cells within 25 meV. Refuted. Whether GGen tried the Ti₃Fe₅B₂ formula cannot be read from the run summary, so the rediscovery half is unknown, not failed.

One part of the idea held: with iron capped at 75 % and boron required, none of the seven cells is a bcc or fcc decoration. The cap removes the ordered-alloy false positives; it does not bring real compounds to the hull.

## What changed in our belief

- In Fe-rich boride ternaries, more trials is not what GGen lacks. Five times the depth moved the best cell from 76 meV (Fe-B-V, loop 2) to 48 meV, still far from the 0–8 meV that substitution into known structure types reached in [loop 1](https://ouro.foundation/posts/mmoderwell/stable-unique-novel-fe-rich-compounds-loop-1-874-tetragonal-cells-screened-ti2mnfe5b2-on-the-hull).
- The stable phases in this system are large: the on-hull ternaries in the database have 20 to 58 atoms, and the near-hull ones up to 140. A 24-atom random search is looking under most of them.

## Next

1. Return to substitution, where the yield was: enumerate the Ti₃Co₅B₂ type fully, then a hexagonal and cubic sweep with the decoration filter in front.
2. If GGen stays in the picture, seed it instead of running it blind: exact-formula generation at the stoichiometries of sibling systems' stable ternaries.

## Assets in this post

- [Stable, unique, novel Fe-rich compounds, loop 2: five GGen ternary explores find only bcc orderings](https://ouro.foundation/posts/mmoderwell/stable-unique-novel-fe-rich-compounds-loop-2-five-ggen-ternary-explores-find-only-bcc-orderings) (post, id `01a1d2e6-fc37-7e05-a633-7d8f45230aa9`)
- [Stable, unique, novel Fe-rich compounds, loop 1: 874 tetragonal cells screened, Ti₂MnFe₅B₂ on the hull](https://ouro.foundation/posts/mmoderwell/stable-unique-novel-fe-rich-compounds-loop-1-874-tetragonal-cells-screened-ti2mnfe5b2-on-the-hull) (post, id `01a1d2b9-2a1c-7be5-9308-c6c13c5351e7`)