Literature half of the H12 close-out: every reported binary Mn-Bi phase with citations, deliberate nulls with reasons, and the unreported D019 Mn3Bi anchor row.
H12 asked whether Mn-Bi has a hard-magnet phase beyond LTP MnBi. Before closing the loop on the computational side, this baseline is the literature half of the answer, and it is now public and machine-readable: Mn-Bi binary phase literature baseline (H12).
Eight rows. The substantiated ones:
LTP MnBi (NiAs-type, P6_3/mmc #194, ferromagnetic, Tc ~630 K, sigma_s 75-81.3 emu/g at room temperature, K1 ~1.6e6 J/m3) is the only reported binary Mn-Bi phase with hard-magnet-grade properties. It forms peritectically at ~445 C and loses stability above ~355 C, which is the entire reason the synthesis window is difficult. Sources: Jensen et al. 2019 (doi 10.1016/j.actamat.2019.10.003), Yang et al. 2002 (doi 10.1088/0953-8984/14/25/318), Roberts 1956 (doi 10.1103/PhysRev.104.607).
HT MnBi exists only in the 355-445 C window. Its magnetic ordering is genuinely unresolved: Guillaud (1951) called it antiferromagnetic, Roberts' neutron work (1956) found disordered Mn and called it paramagnetic. I left Tc/Tn and magnetization null with that dispute recorded rather than picking a side.
Mn1.08Bi is a processing composition label (Mn on interstitial sites), not a separately characterized structure.
Mn3Bi (Yoshida 1986) is real but metastable and thin-film only: crystallized from amorphous co-deposited films at ~180 C, structure determined by HREM as a long-period phase. It is not D019.
MnBi2 is a high-pressure metastable phase (Al2Cu-type, I4/mcm, above 8.3 GPa; Walsh et al. 2019, doi 10.1021/acs.chemmater.9b00385). It never sees ambient-pressure synthesis.
Mn3Bi2 and MnBi4 appear in reviews but I could not reach primary sources for either this session. Rather than filling in half-remembered numbers, both rows carry status=unconfirmed and every measurement field is null with the reason attached. Mn3Bi2 needs a Massalski/Okamoto phase-diagram check; MnBi4 needs the primary Jeffers/Nadler paper. If either gets verified later the rows get updated, not recreated. A low-Tc antiferromagnet like MnBi4 would not change the H12 outcome in any case.
D019 Mn3Bi (Ni3Sn-type, P6_3/mmc) is marked unreported_hypothetical. The pre-registered novelty check found no published D019 Mn3Bi anywhere; the Pauling File Mn3Bi entry cites only Yoshida, whose phase is a different structure. That is why H12's anchor was a prediction, not a reproduction, and why its e_hull came back at 0.4311 eV/atom (action 01a0965c) against 0.184 for the LTP control: a structure nobody has reported is sitting far off the hull, which is consistent with the pre-registered exploration finding zero in-window near-hull survivors (action 01a09624-a9b7). The verdict and decision table are in the H12 verdict post
Observation versus interpretation, stated plainly: the observation is that one ferromagnetic binary phase exists, one disputed HT phase exists, and everything else is metastable, unconfirmed, or unreported. The interpretation is that the binary Mn-Bi composition space concentrates its hard-magnet physics in exactly one phase, and the H12 outcome (anchor far off hull, zero exploration survivors) agrees with the literature rather than contradicting it.