phenomenon · claim-type · cross-domain-transfer · mechanism · claim-relation · replication-status · limitation — grounded in the full text| phenomenon | a reference standard whose internal disagreement is nearly as large as the error it is being used to measure— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | |
| claim-type | method— “Open Quantum Materials Database (OQMD) is a high-throughput database currently consisting of nearly 300,000 density functional theory (DFT) total energy calculations of compounds from the Inorganic Crystal Structure Database (ICSD) and decorations of commonly occurring crystal structures. To maximise the impact of these data, the entire… | |
| method — evidence | — “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” | |
| object of study — evidence | — “Open Quantum Materials Database (OQMD) is a high-throughput database currently consisting of nearly 300,000 density functional theory (DFT) total energy calculations of compounds from the Inorganic Crystal Structure Database (ICSD) and decorations of commonly occurring crystal structures. To maximise the impact of these data, the entire… | |
| research question — evidence | — “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | |
| contribution — evidence | — “In this paper, we outline the structure and contents of the database, and then use it to evaluate the accuracy of the calculations therein by comparing DFT predictions with experimental measurements for the stability of all elemental ground-state structures and 1,670 experimental formation energies of compounds. This represents the largest… | |
| transfer | from measurement theory: inter-rater reliability logic from measurement theory - asking how far two independent determinations of the same quantity sit from each other before scoring a third against either— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | transfers[0] |
| mechanism | measure the ruler before blaming the thing measured the apparent DFT error is 0.096 eV/atom. The authors then measured how far different experimental determinations of the SAME formation energy sit from each other and got 0.082. Almost the whole gap is the width of the reference. THE CONTROL IS THAT THE STANDARD WAS ASKED HOW WELL IT AGREES WITH ITSELF, and almost nobody asks— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | mechanisms[0] |
| mechanism | the calculation closer to experiment than experiment is to itself on the 75 intermetallic compounds shared by the two thermochemical databases, the databases differ by 0.082 eV/atom and OQMD sits 0.071 from experiment. A model cannot be scored below the noise floor of its reference, and here it is already under it— “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” | mechanisms[1] |
| mechanism | an open derivative of a closed source the entire OQMD is downloadable without conditions or limitations, and it is computed from crystal structures obtained through a partnership with the ICSD. THE OPENNESS IS OF THE CALCULATION, NOT OF THE MEASUREMENT IT STARTED FROM - which is exactly the position the corpus itself is in— “Using experimentally measured crystal structures obtained from our partnership with the Inorganic Crystal Structure Database (ICSD),17,18 we have created a new database of DFT-relaxed structures and total energies, which is called the Open Quantum Materials Database (OQMD).” | mechanisms[2] |
| mechanism | a known blind spot, named by physics rather than by residual the elements whose predicted ground state is wrong are the ones held together by van der Waals forces, which the semi-local functionals omit by construction. The error is attributed to a missing term in the theory rather than to a fitting failure, and the paper says which elements and why— “For all elements in the first group above, the ground-state structure cannot be determined reliably with (semi)-local exchange-correlation functionals used in DFT because of the lack of van der Waals interactions, and can likely be corrected by their inclusion.” | mechanisms[3] |
| mechanism | prediction as the leftover of a comparison having compared what is known, the same stability analysis over ICSD compounds and hypothetical structures yields about 3,200 compounds predicted to exist that have never been characterised. The negative space of the experimental record, read off the same calculation— “Finally, we evaluate the stability of compounds in the OQMD (including compounds obtained from the ICSD as well as hypothetical structures), which allows us to predict the existence of ~ 3,200 new compounds that have not been experimentally characterised and uncover trends in material discovery, based on historical data available within the… | mechanisms[4] |
| qualifies | the practice of reporting DFT accuracy as a single error against experiment, by showing the reference disagrees with itself by nearly as much— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | claim_relations[0] |
| critiques | the two experimental thermochemical databases, which differ by 0.082 eV/atom on the compounds they share— “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” | claim_relations[1] |
| distinguishes-from | the Materials Project, the Computational Materials Repository and AFLOWLIB, the neighbouring high-throughput efforts— “There are other efforts in the high-throughput calculation of compounds from large crystal structure databases, including the Materials Project,11,24 the Computational Materials Repository16 and AFLOWLIB.” | claim_relations[2] |
| predicts | the existence of about 3,200 compounds that have not been experimentally characterised— “Finally, we evaluate the stability of compounds in the OQMD (including compounds obtained from the ICSD as well as hypothetical structures), which allows us to predict the existence of ~ 3,200 new compounds that have not been experimentally characterised and uncover trends in material discovery, based on historical data available within the… | claim_relations[3] |
| sense | the DFT error - AS APPARENT: 0.096 eV/atom mean absolute error against experimental formation energies— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | senses[0] |
| sense | the DFT error - AFTER THE REFERENCE IS CHECKED: a significant fraction of it attributable to experimental uncertainty, because different experimental measurements of the same quantity differ by 0.082 eV/atom— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | senses[1] |
| sense | agreement - BETWEEN TWO EXPERIMENTAL DATABASES: 0.082 eV/atom on the 75 intermetallic compounds they share— “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” | senses[2] |
| sense | agreement - BETWEEN OQMD AND EXPERIMENT: 0.071 eV/atom on the same class, which is closer than the two experiments are to each other— “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” | senses[3] |
| sense | `open` - AS OQMD MEANS IT: the entire data set downloadable without any conditions or limitations— “We intend the current data set to be freely available, in its entirety, to the scientific community without any conditions or limitations. It is currently available for download at www.oqmd.org/download.” | senses[4] |
| sense | `open` - AS THE SOURCE IS: the structures come from the ICSD by partnership, and that database is not the thing being given away— “Using experimentally measured crystal structures obtained from our partnership with the Inorganic Crystal Structure Database (ICSD),17,18 we have created a new database of DFT-relaxed structures and total energies, which is called the Open Quantum Materials Database (OQMD).” | senses[5] |
| control | the deviation between different experimental measurements of the same formation energy, computed wherever multiple sources exist, before any error is attributed to the calculation — held— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… — rules out the whole model-versus-experiment residual being read as model error - the reference's own spread is 0.082 against an apparent 0.096— “The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a surprisingly large mean absolute… | controls[0] |
| control | the two experimental thermochemical databases compared on the 75 intermetallic compounds they have in common — held— “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” — rules out a single compilation standing for 'experiment' - two of them disagree by more than the calculation differs from either— “This experiment the 75 intermetallic compounds common to both databases gives a MAE of 0.082 eV/atom, whereas the MAE of OQMD formation energies for intermetallic compounds is 0.071 eV/atom (using ‘fit-none’ chemical potentials).” | controls[1] |
| control | elements whose predicted ground state is wrong grouped by physical cause - missing van der Waals interactions, and f-electrons - rather than reported as residual — held — rules out a list of failures with no account of them; each group is attached to a known limitation of the functional Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[2] |
| control | higher-cutoff calculations run on the noble gas and molecular solids to test whether the discrepancy is a convergence artefact — partial Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. — rules out nothing here - the recomputation reproduces the experimental ground states for He, F and Ar, but the change cannot be substantiated because van der Waals is still missing Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[3] |
| control | the entire data set published for download without conditions or limitations, so the comparison can be repeated by anyone — held — rules out a comparison nobody can repeat - the whole data set is published without conditions, so the numbers can be checked by anyone who doubts them Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[4] |
| weight | the practice of reporting DFT accuracy as a single error against experiment, by showing the reference disagrees with itself by nearly as much — 0.95 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[0] |
| weight | the two experimental thermochemical databases, which differ by 0.082 eV/atom on the compounds they share — 0.95 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[1] |
| weight | the Materials Project, the Computational Materials Repository and AFLOWLIB, the neighbouring high-throughput efforts — 0.9 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[2] |
| weight | the existence of about 3,200 compounds that have not been experimentally characterised — 0.95 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[3] |
| audit | DFT —distinct-from→ experiment — Audit 2026-09-28: DOUBTFUL - read against its span and kept, but DFT is closer to one experiment than the other; distinct-from is loose. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[2] |
| differs in (stated by the tagger, no quotation) | DFT —distinct-from→ experiment — whether a residual is model error or reference spread | concept_edges[2] |
| relation | DFT —distinct-from→ experiment — where two experiments disagree, the calculation is often much closer to one of them than they are to each other, so the residual cannot simply be read as the calculation's error Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[2] |
| weight | DFT —distinct-from→ experiment — 0.95 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[2] |
| outcome | control — held Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[0] |
| outcome | control — held Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[1] |
| outcome | control — held Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[2] |
| outcome | control — partial Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[3] |
| outcome (stated by the tagger, no quotation) | control — held Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[4] |
| limitation | the ground-state structure of a whole group of elements cannot be determined reliably with the semi-local functionals used, because van der Waals interactions are missing Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[0] |
| limitation | for noble gas and molecular solids the change in predicted stabilities cannot be substantiated, since van der Waals contributes a significant portion of the energy Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[1] |
| limitation | where two experimental databases disagree there is no principled way to say which measurement is wrong, so the residual cannot be fully assigned Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[2] |
| limitation | the structures are obtained from the ICSD by partnership; the openness of the derived data set does not extend to the source Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[3] |
finding · quantity · variable · definition · key-term — grounded in the full text| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[0] |
| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[1] |
| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[2] |
| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[3] |
| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[4] |
| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[5] |
| finding | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[6] |
| quantity | eV/atom - the apparent mean absolute error between experiment and the calculations Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[0] |
| quantity | eV/atom - how far different EXPERIMENTAL measurements of the same quantity sit from each other Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[1] |
| quantity | eV/atom - OQMD against experiment on intermetallics, closer than the two experimental databases are to each other Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[2] |
| variable | formation energies Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[0] |
| definition | OQMD Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[0] |
| concept | OQMD — not defined in this paper's own words; nearly 300,000 DFT total-energy calculations of ICSD compounds and prototype decorations, downloadable in full without restrictions Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[0] |
| concept | ICSD — not defined in this paper's own words; the Inorganic Crystal Structure Database - the experimentally measured structures OQMD is computed from, obtained by partnership rather than openly Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[1] |
| concept | DFT — not defined in this paper's own words; density functional theory - the calculation whose error against experiment this paper set out to measure and partly reassigned Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[2] |
| concept | formation energies — not defined in this paper's own words; the compared quantity; measured values of the same compound differ between thermochemical databases by about as much as DFT differs from either Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[3] |
| concept | experimental uncertainties — not defined in this paper's own words; the share of the apparent DFT error that belongs to the reference rather than to the calculation - measurable only because multiple sources exist Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[4] |
| concept | databases — not defined in this paper's own words; the two experimental thermochemical compilations whose 75 shared intermetallic compounds disagree by 0.082 eV/atom Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[5] |
| concept | van der Waals — not defined in this paper's own words; the interaction the semi-local functionals omit - the named reason a whole group of elemental ground states cannot be determined reliably Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[6] |
| concept | experiment — not defined in this paper's own words; the reference the calculation is scored against - and, on the compounds where two determinations exist, a thing that disagrees with itself Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[7] |
| concept | AFLOWLIB — not defined in this paper's own words; one of the neighbouring high-throughput efforts named alongside the Materials Project and the Computational Materials Repository Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[8] |
| MAE | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[0] |
When we have changed our mind. Some entries in the table begin with a word in capitals and the reason for it. EVIDENCE CORRECTED — the finding still stands, but we had quoted the wrong sentence from the paper, and the quotation has been replaced with the right one. RETRACTED — the entry itself was wrong; it stays on the page, marked, with the reason, rather than being deleted. WITHDRAWN AND REPLACED — the entry was wrong, and a corrected version of it appears in the entries below. Each mark carries its own reason, in brackets, because the reasons differ from one entry to the next. An entry we have WITHDRAWN is removed from this page and kept in the record, with its reason. A line reading Audit and a date is a later re-reading of the entry against its whole sentence: DOUBTFUL means it was kept, and the reason says what is loose about it. Quotation marks inside the tagger's sentence. Where a tag is the tagger's own sentence, a phrase in quotation marks inside it is borrowed from the paper — the tagger's wording around it is not. The paper's own sentence is the evidence quote for that row; on this page it is withheld with the article, and the article is at its publisher. Nothing inside quotation marks anywhere on this page is ours: if it is quoted, it is the paper's. Whose words a concept carries. A concept entry records a term the paper itself uses, so the term, the sense given for it, and its evidence are the paper's own words, quoted where the paper fixes them. This is the opposite of a sense entry in the tag table, which is the tagger's sentence about how the paper uses a term. Where a concept entry could not be grounded in the paper's words, the entry says so on its own row.
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