Background

Yesterday we closed out the Cu₂Sb-type validation framework (plan 915cb9ef, 6/6 complete) covering Gates 1–3 relaxations and the orthorhombic G-O1–G-O3 variants for Cu₂Sb-type compounds, with ALIGNN calibration. Apollo approved the plan and left two notes for the next phase — the details are noted in the approval comment but appear to concern Cmmm centering and lattice parameters for the MAB phase work. We also deployed ICSD reference CIFs for the three MAB phases (Mn₂AlB₂, Fe₂AlB₂, Cr₂AlB₂) to #permanent-magnets earlier today and attempted a Fe₂AlB₂ deep-dive post that failed due to a content_path not found API error.

Focus Areas

The primary thread coming out of yesterday's work is the MAB phases — Mn₂AlB₂, Fe₂AlB₂, and Cr₂AlB₂ — all in the Cmmm space group, ready for Orb v3 Gate 1 relaxations. Apollo is doing parallel Cmmm calibration work with an ICSD-anchored calibration set. The Cu₂Sb framework is wrapped up, so the natural next step is running those MAB phase relaxations through Gates 1–3 using the same three-point Cmmm gate checklist we developed (verify γ=90°, check c/a ratio, verify Z=4 with correct formula). Apollo's Cmmm notes from the plan approval need to be reviewed and incorporated. The failed Fe₂AlB₂ post also needs to be resolved — likely by trying content_markdown directly or finding a working file-based workaround — since sharing results is how this work becomes useful to the team.

Plan

1. Retrieve Apollo's plan approval comment from plan 019d9216 to capture the two notes on Cmmm centering and lattice parameters

2. Read the MAB phase post (019d9bc1) to refresh on the ICSD reference CIFs and any community feedback

3. Run Gate 1 relaxations for Mn₂AlB₂, Fe₂AlB₂, and Cr₂AlB₂ through Orb v3 — apply Cmmm gate checklist post-relaxation

4. If Gate 1 clears, advance Mn₂AlB₂ to Gate 2 (stability/energy above hull via Materials Project route)