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"energy_per_atom": -4.574425605, "entries_at_x": 10, "formula": "Na1 O3", "nsites": 4, "phase": "oqmd-15265", "phase_kind": "structure", "spacegroup_number": 44, "spacegroup_symbol": "Imm2", "theoretical": false, "x": 0.75 }, { "collinear": false, "degenerate": [], "energy": -0.5603043751605965, "energy_per_atom": -4.608729592857143, "entries_at_x": 1, "formula": "Na1 O6", "nsites": 7, "phase": "oqmd-2131624", "phase_kind": "structure", "spacegroup_number": 1, "spacegroup_symbol": "P1", "theoretical": true, "x": 0.8571428571428571 }, { "collinear": false, "degenerate": [], "energy": 0.0, "energy_per_atom": -4.84445622625, "entries_at_x": 29, "formula": "O1", "nsites": 8, "phase": "oqmd-20034", "phase_kind": "structure", "spacegroup_number": 12, "spacegroup_symbol": "C2/m", "theoretical": false, "x": 1.0 } ] } ], "mp_agreement": { "comparable": false, "comparable_note": "is_stable is derived by the extraction, not an upstream flag, so comparing it against a hull recomputed from the same energies tests the derivation rather than the data", "max_abs_delta_energy_above_hull": 7.152189951398213e-10, "only_mp_stable": [ "oqmd-ref-Na", "oqmd-ref-O" ], "only_ours_stable": [], "stable_sets_match": false }, "provenance": { "above_hull_window_eV": 0.05, "builder_version": 1, "collinear_tol": 1e-12, "correction_model": "OQMD fit-partial ('standard' fit, applied upstream by OQMD; none added)", "degenerate_tol": 1e-06, "entry_pool": "all_nondeprecated", "is_stable_source": "derived", "observed_at": "2026-09-05T17:02:03Z", "snapshot_scope_elements": [], "snapshot_scope_kind": "full", "snapshot_sha256": "2a9393262c52ec35600424236c352a4cdb3291c8b25c1c6588f5e62abe8e0d8d", "source_release": "qmdb_v1_8_022026", "stability_tol": 0.0001, "thermo_type": "standard", "upstream_energy_corrections": "OQMD 'standard' fit (fit-partial of Kirklin et al. 2015): elemental reference energies of a subset of elements fitted to experimental formation enthalpies, applied by OQMD" }, "reference": { "kind": "dft_fitted_elemental_reference_0K", "per": "atom", "temperature_K": 0.0, "units": "eV/atom" }, "schema_version": 1, "system_id": "NA-O", "x_element": "O" }