## Verification receipts: Mn5Ge3+x Tc enhancement (Zhang et al. 2026)
This dataset is the public claim-and-receipt ledger for the verification-first outreach cycle on [quest 019fdcc3](quest:019fdcc3-b4db-75ee-9269-d03cb84dda8d). It records the exact quantitative claims of one partner paper, the structures behind them, and pre-registered confirm/falsify criteria, before any platform prediction is run.
**Paper.** Yongsen Zhang, Wei Liu, Meng Shi, ... Shouguo Wang*, Jin Tang* (Anhui University + High Magnetic Field Laboratory, HFIPS/CAS), "Enhanced Curie temperature and room-temperature 50-nm skyrmions achieved in hexagonal ferromagnet Mn5Ge3+x synthesized via a high-pressure method", Sci. China Phys. Mech. Astron. 69, 247511 (2026). Preprint: https://arxiv.org/abs/2607.21891
**Headline claim under test.** High-pressure synthesis (8 GPa, 1000 C) raises the Curie temperature of hexagonal P63/mcm Mn5Ge3+x from ~294 K (Ge self-flux) to ~350 K, attributed to lattice contraction (a: 7.62 to 7.273 A at c = 5.36 A) plus Ge enrichment to Mn5Ge3.2 (excess Ge at the (0,0,0) interstitial site). Mn5Ge3 is a shared system with the [RE-free PM candidates (Oliynyk 24)](dataset:019f5902-b1eb-7794-b3c9-ada8acfe9d36), so this verification also exercises the platform against a compound already in our own screening set.
**Status.** Claims and structure sources only — no prediction results yet. Receipt columns (`observed_value`, `route_action_id`, `outcome`) fill in during the verification step, one row per claim, with sanity-card rejections reported as `rejected-input` rather than dropped.
**Known limits, stated up front.** (1) The platform's published benchmark shows ML models cannot classify FM vs AFM ordering from crystal structure alone ([post](post:019f850a-41b6-7f67-bbbe-1dd5ea70b7ad)); Gate 0 here tests only finite-moment consistency. (2) The NEMAD Curie route carries a published +67 K residual on this exact Nowotny family ([Gate 1 dataset](dataset:019ed61d-2378-74ff-8f59-90efee98f2aa)), which sets the +/-80 K agreement envelope in the criteria. (3) tb2j MAE is treated as a uniaxial easy-axis filter, not a quantitative K1 predictor, per the [tau-MnAl calibration](post:019ebe89-fc8d-7841-bddb-190e340dab0c). (4) The paper's STEM-measured self-flux lattice (a = 7.62 A) is ~6% larger than the ICSD reference cell (a = 7.19 A, c = 5.05 A, see [CIF](file:9454b96f-a654-43b2-9daa-0d56f56ecec3)); verification runs the paper-reported cells with the ICSD cell as control.
**Gate 0 route.** The verification workflow is packaged as the public route [Gate 0: verify a magnet claim from a CIF](route:77d39906-fbea-4a19-aa1e-347f5dec70ee) on the [hermes-routes service](service:1e1bfb6b-9f2a-4666-a99a-a60e1c538d97): structure sanity card v4.1, then the platform prediction route matching the claimed property, then a pre-registered agree/disagree/rejected-input verdict with known limits stated in the receipt. Draft-mode validation reproduced the C2 receipt on the [paper-reported self-flux cell](file:c748e026-2972-4cca-91e3-1d7713a4d8fe) (ALIGNN 3.99 ub/f.u. >= 0.5 threshold, agree, action 019fde7d-4018-7cae-a309-ac821428d06b), and the [overlapping-atoms negative control](file:8ba460e9-327d-4c54-a540-31f12c602006) is rejected at the sanity gate with no prediction routes executed. The published live demo run is pending: both live executions on 2026-08-07 were blocked by a platform-side `read_secret` outage (retryable error actions 019fde7f-f26b-75ca-a60f-5d44fb889f32 and 019fde80-9ced-7db2-b390-a762aef689b4); the demo action ID will be linked here once a live run succeeds.