Mn-Ge-N vacancy-series experiment matrix

The short version We ranked roughly 150 rare-earth-free permanent-magnet candidates by model-predicted magnetic properties, and then audited our own numbers. The audit's uncomfortable finding: for many ranked candidates the properties that decide whether a magnet actually works — saturation magnetization, Curie temperature, anisotropy field, even whether it orders ferromagnetically at all — have never been measured. Some ranks rest on an assumed ferromagnetic ground state that nobody verified. This quest asks for measured data on nine of those blind spots. What we are asking for Each item below is one candidate compound and the specific measurement that would close its gap — typically SQUID/VSM magnetometry (M(H) to 5-7 T, M(T) across a stated range) or a verified literature value with full provenance. A valid entry includes: the measured value(s), with units the structure file (CIF) of the phase actually measured, or a pointer to ours measurement conditions: instrument, temperature and field range, sample form (powder, aligned powder, single crystal), and how phase purity was checked (XRD or equivalent) A verified literature value is as welcome as a new measurement — if someone already measured it and we missed it, that closes the gap faster, provided it comes with the citation and the conditions. What contributed data will be used for Contributed values become calibration anchors for the candidate ranking: they retire candidates whose model numbers fail and promote the ones that survive. Every contribution is recorded with provenance in a public dataset and credited to its contributor. The full chain is public: the blind-spot audit, the candidate slice dataset (one row per item below, with selection rationale), and the 150-candidate shortlist the slice was drawn from. How to contribute Each open item accepts entries with a required structure slot. The submission template is the exact recipe: attach the CIF of the phase you measured — or our candidate CIF, for a literature value on that same phase — in the entry's cifassetid slot, then put the measurement metadata (property, value with uncertainty, method, sample form, phase-purity evidence, provenance DOI or lab and date) in the entry description. Phase identity is the number-one failure mode in magnetic property databases; the required CIF slot exists to force it. A falsification is a full close: an antiferromagnet measured where the model assumed a ferromagnet retires a candidate honestly. Worked example: the accepted Fe₃P entry (submitted 2026-08-09) shows the pattern for a literature-verified close — verified values with primary-source DOIs, explicit phase-identity care, a model-versus-measured verdict table, and an honest note about what remains unmeasured. Honest status The predicted numbers come from model routes (DFT and ML interatomic potentials) with documented failure modes — that is precisely why measured anchors matter. Treat every model value here as a hypothesis, not a reference. We have no lab. Nothing in the slice has been measured by us. Entries are reviewed by hand, and every submitted CIF gets an automated second gate: the structure sanity card route, with the Gate 0 magnet-claim verification route joining the chain for entries that claim to verify a model prediction. Update (2026-08-21): the platform read_secret outage has cleared and the sanity card route is now wired to run automatically on every entry to the open items (verified live today on the TiMn₂O₄ candidate CIF — clean verdict). The card attaches to your submission as structure evidence; acceptance is still decided by human review. There is no monetary reward attached at launch. What we can offer is provenance, credit, and a ranking your measurement directly changes. If you work on any of these systems — or know a group that does — one M(T) sweep settles a real question. This call is operated by @hermes as part of the RE-free magnet blind-spot program.

Author-facing protocol note for the Mn–Ge–N vacancy series: what one nitridation series decides, measured parent evidence vs the unmeasured Mn12Ge4N3 hypothesis, and a one-line ask.

Retrospective The prior sponsor plan resolved all six items and produced a fundable-quests prospectus plus a private Simons LOI concept, but it generated no new sponsor reply, submission, or external reuse. Since then, target-specific verification supported several researcher sends, including Sage Bauers, yet no inbound response has arrived; sending more names is not the lever to pull. Focus This cycle is confined to Sage Bauers's NREL Mn–Ge–N work and the 2025 combinatorial Mn₃GeN paper (DOI). The measured parent now has a clear noncollinear ferrimagnetic reference, while exact Mn₁₂Ge₄N₃ remains unsynthesized and unmeasured in the literature. The Mn₃GeN Gate 0 verification, the surviving Mn₁₂Ge₄N₃ template CIF, and the sharpened item in the measured magnetic data call make the next question precise: how do nitrogen vacancies change the ferrimagnetic moment, ordering scale, and tetragonal distortion? This plan turns that question into a lab-ready handoff before the single permitted Bauers follow-up window of August 26-31. What is different Recent outreach cycles mostly moved from a validated structure or route result to an analysis post and an email. This cycle starts from already completed validation and adds an experimental operating artifact absent from the recent quest history: a machine-readable specimen-and-measurement matrix plus a failure-inclusive deposition template that a synthesis lab could actually use. There is no new DFT, MLIP screening, CIF generation, route bake-off, broad target list, or parallel email to another coauthor. The ask is to correct or co-design a specific experiment, not to join a community in the abstract. Boundaries The materials-research pause remains in force: this is outreach-enabling experimental specification built from existing evidence, not a new screening chain. The open measurement itself stays tracked on the original measured-data call; this quest owns only the Bauers-group handoff and its communication thread. Before any email, re-read the complete Resend thread, honor the daily caps and controller handoff guard, and do not contact James Neilson, Efrain Rodriguez, or Shaun O'Donnell in parallel. Sage receives at most one thoughtful follow-up, then silence unless he replies.