phenomenon · claim-type · cross-domain-transfer · mechanism · claim-relation · replication-status · limitation — grounded in the full text| phenomenon | a method whose defining choice is to give an element ONE description everywhere, and whose parameter sets have consequently forked into two populations that cannot be mixed— “In order to explain the existence of branches within a common functional form, we must consider that ReaxFF does not employ atom typing in contrast to popular non-reactive force-fields like strategies, AMBER25 and CHARMM.26 For example, there is only one oxygen type in ReaxFF regardless of the chemical environment in which the oxygen atom… | |
| claim-type | method— “Alternatively, empirical interatomic potentials that are based on classical principles require significantly fewer computational resources, which enables simulations to better describe dynamic processes over longer timeframes and on larger scales. Such methods, however, typically require a predefined connectivity between atoms, precluding… | |
| method — evidence | — “The 2008-C/H/O parameter set was trained against the entire 2001-C/H training set, while the 2010 and 2011 Si/O/H parameterisations (Fogarty et al.15 on the ‘aqueous branch’ and Neyts et al.16 on the ‘combustion branch’) were validated against the full 2003-Si/O/H training set.” | |
| object of study — evidence | — “Alternatively, empirical interatomic potentials that are based on classical principles require significantly fewer computational resources, which enables simulations to better describe dynamic processes over longer timeframes and on larger scales. Such methods, however, typically require a predefined connectivity between atoms, precluding… | |
| research question — evidence | — “Although a ReaxFF description exists for these elements, one cannot simply use these parameter sets in any combination and expect to obtain satisfactory transferability. As shown in Figure 2, there are currently two major groupings (i.e., the ReaxFF branches) of parameter sets that are intra-transferable with one another: (1) the combustion… | |
| contribution — evidence | — “Although a ReaxFF description exists for these elements, one cannot simply use these parameter sets in any combination and expect to obtain satisfactory transferability. As shown in Figure 2, there are currently two major groupings (i.e., the ReaxFF branches) of parameter sets that are intra-transferable with one another: (1) the combustion… | |
| transfer | from quantum chemistry: the bond-order concept from chemical bonding theory, used as the empirical function of interatomic distance that lets a classical potential break bonds— “Alternatively, empirical interatomic potentials that are based on classical principles require significantly fewer computational resources, which enables simulations to better describe dynamic processes over longer timeframes and on larger scales. Such methods, however, typically require a predefined connectivity between atoms, precluding… | transfers[0] |
| mechanism | one type, two branches ReaxFF's defining choice is that an element has ONE description regardless of environment, which is what lets an atom migrate between phases mid-simulation. The cost is that a parameter set cannot be specialised without changing the shared atom-level parameters - so the specialisation became a BRANCH instead of a TYPE. REFUSING TO SPLIT THE VOCABULARY SPLIT THE PARAMETER SETS— “In order to explain the existence of branches within a common functional form, we must consider that ReaxFF does not employ atom typing in contrast to popular non-reactive force-fields like strategies, AMBER25 and CHARMM.26 For example, there is only one oxygen type in ReaxFF regardless of the chemical environment in which the oxygen atom… | mechanisms[0] |
| mechanism | the scope decision that became a failure liquid water was not a development aim for the 2008 combustion field because every intended application was above the boiling point. That is a defensible scope decision at the time and it is why the field fails on liquid water in 2009, and why a second branch had to exist— “The lack of transferability between branches is evident in the performance of the 2008-C/H/O combustion force-field,2 which accurately describes water as a gas-phase molecule yet fails to describe water as a liquid. During development at that time, describing liquid water was not a particular aim for ReaxFF. Since all intended applications… | mechanisms[1] |
| mechanism | a fork that cannot be undone cheaply parameter sets on the same branch combine by fitting only the bond and angular terms between the newly combined elements; across branches it takes extensive refitting, and combustion-to-aqueous is the easier direction. THE ASYMMETRY IS A FACT ABOUT THE FITTING HISTORY, not about the chemistry— “Parameter sets on the same development branch can be directly combined, where the required force-field fitting consists only of parameterising bond and angular terms between the newly combined elements. Transferring parameters between branches, however, requires more extensive refitting.” | mechanisms[2] |
| mechanism | branches merge by refitting, not by agreement several independent branches - B/N/H, Ni/C/H - began as non-transferable descriptions and were later merged into combustion or aqueous through extensive refitting. A vocabulary reconciled by redoing the work rather than by declaring the terms equivalent— “Typically these sets began as non-transferable ReaxFF descriptions constituting independent development branches, but many have later been merged, through extensive refitting, with the combustion (C/B/N/H/O)34 or aqueous branches (Ni/C/H/O).” | mechanisms[3] |
| mechanism | accuracy traded for scale, on purpose QM structure and energy data train the empirical field, which then runs at scales orders of magnitude beyond what QM can reach. The potential is a compression of the quantum calculation, and every branch is a different compression of a different part of it— “To alleviate this issue, QM structure and energy data are used to train empirical force fields that require significantly fewer computational resources, thereby enabling simulations to better describe including reactive dynamic processes. Such empirical methods, force-field (ReaxFF),1 trade accuracy for lower computational expense, making it… | mechanisms[4] |
| distinguishes-from | AMBER and CHARMM, non-reactive force fields that type atoms by chemical environment— “In order to explain the existence of branches within a common functional form, we must consider that ReaxFF does not employ atom typing in contrast to popular non-reactive force-fields like strategies, AMBER25 and CHARMM.26 For example, there is only one oxygen type in ReaxFF regardless of the chemical environment in which the oxygen atom… | claim_relations[0] |
| qualifies | ReaxFF's own transferability claim, by stating that parameter sets fall into two branches that are only intra-transferable— “Although a ReaxFF description exists for these elements, one cannot simply use these parameter sets in any combination and expect to obtain satisfactory transferability. As shown in Figure 2, there are currently two major groupings (i.e., the ReaxFF branches) of parameter sets that are intra-transferable with one another: (1) the combustion… | claim_relations[1] |
| builds-on | quantum-mechanical structure and energy data, used as the training data for every parameterisation— “To alleviate this issue, QM structure and energy data are used to train empirical force fields that require significantly fewer computational resources, thereby enabling simulations to better describe including reactive dynamic processes. Such empirical methods, force-field (ReaxFF),1 trade accuracy for lower computational expense, making it… | claim_relations[2] |
| sense | an oxygen atom - IN ReaxFF's DESIGN: one type, treated with the same mathematical formalism whether it is O2 in gas, water in liquid, or a solid oxide— “In particular, ReaxFF enables simulations involving reactive events at the interface liquid, and gas phases, which is made possible between solid, because the ReaxFF description of each element is transferable across phases. For example, an oxygen atom is treated with the same mathematical formalism whether that oxygen is in the gas phase as… | senses[0] |
| sense | an oxygen atom - IN PRACTICE: described by combustion-branch parameters or by aqueous-branch parameters, which are not directly transferable— “As such, the decision was made to initiate a new branch—the aqueousbranch—that employs the same functional form as the 2008-C/H/O description, but with different O/H atom and bond parameters. This resulted in the creation of a number of parameter sets that are not directly transferable with those on the pre-existing combustion branch, thus… | senses[1] |
| sense | water - UNDER THE 2008 COMBUSTION FORCE FIELD: accurately described as a gas-phase molecule | senses[2] |
| sense | water - UNDER THE SAME FORCE FIELD, AS A LIQUID: not described at all, because liquid water was not a development aim at temperatures above the boiling point 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. | senses[3] |
| sense | a parameter set - WITHIN ITS BRANCH: directly combinable, needing only bond and angular terms between the newly combined elements 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. | senses[4] |
| sense | a parameter set - ACROSS BRANCHES: requiring extensive refitting, with combustion to aqueous the easier direction 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. | senses[5] |
| control | later parameterisations validated against the FULL training sets of the earlier ones they supersede - the 2008-C/H/O set against the entire 2001-C/H training set — 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. — rules out a newer parameter set that is better on its own data and worse on the old - the earlier training set is re-run rather than retired 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] |
| control | water tested in both phases under the same force field, rather than only in the phase the field was built for — failed 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 a force field that looks general because it was only asked about the case it was fitted to - testing the other phase is what exposed the branch 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] |
| control | independent branches merged into combustion or aqueous through extensive refitting, with the high-energy-material description reported as merged without an obvious loss in accuracy — 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. — rules out a merge that silently degrades the absorbed branch - the accuracy claim is made explicitly at the point of merging 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 | the same element treated with one formalism across gas, liquid and solid, checked by letting atoms migrate between phases within a simulation — 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. — rules out phase boundaries being imposed by the model rather than by the physics 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 | other ReaxFF implementations developed outside the originating group, noted as existing — absent-stated-about-other — rules out that a result depends on this particular ReaxFF implementation rather than on the force field 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. | controls[4] |
| weight | AMBER and CHARMM, non-reactive force fields that type atoms by chemical environment — 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 | ReaxFF's own transferability claim, by stating that parameter sets fall into two branches that are only intra-transferable — 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 | quantum-mechanical structure and energy data, used as the training data for every parameterisation — 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] |
| differs in (stated by the tagger, no quotation) | combustion branch —distinct-from→ aqueous branch — which O and H parameters, under an identical functional form | concept_edges[0] |
| relation | combustion branch —distinct-from→ aqueous branch — the aqueous branch uses the same functional form as the combustion description with different O/H atom and bond parameters, and its parameter sets are not directly transferable with the pre-existing branch 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[0] |
| weight | combustion branch —distinct-from→ aqueous branch — 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[0] |
| differs in (stated by the tagger, no quotation) | ReaxFF —distinct-from→ CHARMM — whether an atom's parameters depend on the environment it is in | concept_edges[1] |
| relation | ReaxFF —distinct-from→ CHARMM — ReaxFF does not type atoms by chemical environment; CHARMM and AMBER do - which is why one oxygen in ReaxFF has to serve gas, liquid and solid at once 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. 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[1] |
| weight | ReaxFF —distinct-from→ CHARMM — 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[1] |
| audit | gas-phase —distinct-from→ liquid — Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span says the force-field describes water as a gas-phase molecule yet fails for liquid water; 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) | gas-phase —distinct-from→ liquid — which phase the same molecule is in | concept_edges[2] |
| relation | gas-phase —distinct-from→ liquid — the 2008 combustion force field describes water accurately as a gas-phase molecule and fails on liquid water, because liquid water was not a development aim at the temperatures intended 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. 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 | gas-phase —distinct-from→ liquid — 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 — failed 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 — 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[3] |
| outcome (stated by the tagger, no quotation) | control — absent-stated-about-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. | controls[4] |
| limitation | parameter sets cannot be used in any combination and expect satisfactory transferability - there are two branches and they are only intra-transferable 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 | the absence of atom typing makes force-field development significantly more complex 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 | the 2008 combustion force field fails to describe liquid water, and could not be reparameterised for it without changing general and atom-specific parameters 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 | transferring parameters between branches requires extensive refitting, and the direction matters 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] |
| limitation | empirical potentials trade accuracy for computational expense by construction 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[4] |
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 | the C/H/O combustion force field that describes gas-phase water and fails on liquid water 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] |
| variable | transferability 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] |
| variable | bond-order 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[1] |
| definition | ReaxFF 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] |
| definition | aqueous branch 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[1] |
| concept | ReaxFF — not defined in this paper's own words; a reactive force field casting the empirical interatomic potential in a bond-order formalism, so bonds break and form without explicit quantum mechanics 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 | atom typing — not defined in this paper's own words; assigning an atom different parameters by chemical environment - the strategy AMBER and CHARMM use and ReaxFF deliberately does not 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 | CHARMM — not defined in this paper's own words; a non-reactive force field that types atoms by chemical environment - named here, with AMBER, as the contrast that explains why ReaxFF branched 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 | combustion branch — not defined in this paper's own words; one of the two groupings of ReaxFF parameter sets that are transferable among themselves; describes water as a gas and fails on liquid water 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 | aqueous branch — not defined in this paper's own words; the branch initiated in 2009 for aqueous chemistry - the same functional form with different O/H atom and bond parameters 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 | transferability — not defined in this paper's own words; whether a parameter set can be used with another; intra-branch it is free, cross-branch it requires extensive refitting 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 | gas-phase — not defined in this paper's own words; the state in which the 2008 combustion field describes water accurately 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 | liquid — not defined in this paper's own words; the state the same field fails on - and the reason a second branch exists 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 | training set — not defined in this paper's own words; the QM structure and energy data a parameterisation is fitted or validated against; which set was used is what makes two parameterisations comparable 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] |
| concept | bond order — not defined in this paper's own words; calculated empirically from interatomic distances - the quantity that lets a classical potential represent bonds breaking 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[9] |
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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