Skip to content

Development of a ReaxFF Potential for Carbon Condensed Phases and Its Application to the Thermal Fragmentation of a Large Fullerene

PDF variant

This slug points to an ACS proof PDF. The same scientific text appears in the journal-layout PDF on 2015srinivasan-venue-jp-2014-10274e (papers/Srinivasan_JPC_graphene_2015.pdf).

Summary

This article develops ReaxFF C-2013 by reparametrizing the ReaxFF CHO carbon subset using DFT equations of state for graphite and diamond, formation energies of graphene defects and amorphous regions derived from fullerenes, and related benchmarks. The abstract reports that ReaxFF C-2013 reproduces the graphite atomization energy, the DFT graphite–diamond energy difference and graphite→diamond barrier, and the DFT Stone–Wales barrier in C₆₀(Ih) via concerted C₂ rotation. MD of C₁₈₀ shows exponential-in-time fragmentation; an Arrhenius fit gives 7.66 eV for carbon loss, with C₂ elimination dominant and larger fragments increasingly probable at higher temperature. Motivation includes coal pyrolysis, soot incandescence, graphitic nozzle erosion, and spacecraft ablation.

Methods

Force-field training follows the same DFT → ReaxFF C-2013 protocol described on 2015srinivasan-venue-jp-2014-10274e: graphite/diamond EOS, graphene-defect and amorphous-carbon formation energies tied to fullerene motifs, plus Stone–Wales and phase benchmarks (abstract).

Static QM / DFT uses that DFT database for fit targets and post-fit verification (abstract).

MD application applies ReaxFF C-2013 in NVT reactive MD to a gas-phase C₁₈₀ fullerene (180 carbon atoms), scanning elevated temperatures for Arrhenius analysis of fragmentation rates (abstract). Boundaries: isolated gas-phase fullerene with vacuum padding or large-box PBC as defined in Computational methods on pdf_path. Engine, timestep, thermostat, and production trajectory durations (ps/ns) are tabulated on pdf_path; for pagination-sensitive citations prefer the journal-layout sibling [[2015srinivasan-venue-jp-2014-10274e]]. Barostat / hydrostatic pressure: N/A. Electric field / enhanced sampling: N/A.

Findings

Benchmarks: ReaxFF C-2013 reproduces the DFT targets quoted in the abstract for graphite/diamond thermochemistry and the C₆₀ Stone–Wales barrier.

C₁₈₀ kinetics: Fragmentation decay is exponential in time; an Arrhenius fit yields 7.66 eV for carbon loss; C₂ units dominate while larger fragments become more probable at higher temperature (abstract).

Comparisons: The introduction situates results within prior experimental and simulation literature on fullerene decomposition channels.

Sensitivity: Temperature controls which fragmentation channels dominate beyond simple C₂ shrink-wrap pictures.

Limitations

Proof PDF layout differs from the version of record and can shift pagination relative to 2015srinivasan-venue-jp-2014-10274e. ReaxFF accuracy remains case-dependent outside the fitted carbon chemistry space.

Relevance to group

Penn State and ORNL collaboration on carbon ReaxFF and high-temperature fullerene fragmentation.

Reader notes (navigation)

Citations and evidence anchors

  • DOI: 10.1021/jp510274e; papers/Srinivasan_JPC_graphene_2015_proof.pdf.
  • normalized/extracts/2015srinivasan-venue-research_p1-2.txt (abstract; proof layout).