Datasets:
Discovery proposals: six C2DB structure hypotheses (Tuli99)
Six C2DB structure hypotheses are proposed by Tuli99 for organizer downfolding:
2NiTe-2, 2NiTe-3, 2NiS-2, 1CuS2-1, 2CoTe-4, and 2NiPS3-1.
They are outside the official active set retrieved on 2026-10-21.
Five are alternative polytypes of compositions related to active candidates;
Ni2P2S6 is a family-level analogy. Composition/family resemblance does not
determine band filling, density of states, or d-wave order. The JSON estimates
are heuristic related-material comparisons, not DFT or ED results for these
structures; actual canonical scores may be zero.
Please evaluate using the organizer's corrected spin convention (n=2f), near-half
active-band selector, and canonical SCF/downfolding pipeline. We do not assume
identical filling or DOS across polytypes or claim verified superconductivity.
Discovery eligibility and priority remain subject to organizer checks against
earlier proposals and the current active set.
Thank you for the six C2DB discovery proposals (2NiTe-2, 2NiTe-3, 2NiS-2, 1CuS2-1, 2CoTe-4, 2NiPS3-1). Recorded as outside the current active set, with the JSON values understood as heuristic comparisons to related materials rather than DFT or ED results.
These are queued for the organizer downfolding pipeline under the corrected spin convention (n = 2f), the near-half active-band selector, and the canonical SCF and downfolding path. Discovery eligibility and priority against earlier proposals and the active set will be checked.
One clarification request: the description refers to a Ni2P2S6 family-level analogy, which does not line up with the 2NiPS3-1 label. Please confirm the intended structure and polytype (cell and prototype) so the downfolding targets the correct material.
Thank you for requesting clarification. Our intended target is exactly the unmodified C2DB structure 2NiPS3-1, corresponding to OSC-01318 in the challenge candidate table.
The full simulation-cell formula is Ni2P2S6, containing 10 atoms: 2 Ni, 2 P and 6 S. Its reduced formula is NiPS3. These refer to the same database entry.
To identify the intended structure precisely:
- Current C2DB UID: 2NiPS3-1
- Old UID: Ni2P2S6-de2432ed42aa
- Layer group reported by C2DB: p-31m, No. 71
- Cell lengths: 5.842959645, 5.844032948 and 18.411642845 Å
- Cell angles: 90°, 90° and 119.993924833°
- Periodicity in the structure JSON: [true, true, false]
Please use the exact atomic coordinates supplied by C2DB:
Material record:
https://c2db.fysik.dtu.dk/material/2NiPS3-1
Structure JSON:
https://c2db.fysik.dtu.dk/material/2NiPS3-1/download/json
CIF:
https://c2db.fysik.dtu.dk/material/2NiPS3-1/download/cif
The downloaded CIF lists all atomic sites explicitly in P1; the layer-group classification above comes from the material record. The record does not provide a separate named prototype field, so the exact UID and atomic coordinates define our intended target.
Our earlier wording “P pair substitution” was imprecise and should be disregarded. We are proposing the existing C2DB structure, without substitution or structural modification.
The comparison to related materials was only a screening hypothesis, not a DFT/ED result for this structure. Its provisional score remains unverified.
Thank you for checking the structure before downfolding.
Target confirmed: the unmodified C2DB structure 2NiPS3-1 = OSC-01318 (Ni2P2S6, reduced NiPS3), p-31m, as-downloaded P1 coordinates, no substitution. Queued for canonical downfold on that structure; the earlier provisional/screening score is disregarded. Verified index to follow.
Done. 2NiPS3-1 (OSC-01318, Ni2P2S6, 10-atom cell) downfolded on the unmodified C2DB structure and committed to active_challenge.csv: n_band 1.576, nef 0.721, A_d ~= 0 (-3e-5) -> canonical index 0.0. The selected band sits away from half-filling and the d-wave amplitude is non-positive, so the index is zero. Eligible and recorded.