Skip to content

ReaxFF molecular dynamics simulations of electrolyte–water systems at supercritical temperature (AIP author proof PDF)

Evidence and attribution

Authority of statements

This ingest is an AIP author proof / query PDF (papers/Dasgupta_JCP_2020_supercritical_electrolyte_galley.pdf) with AUTHOR QUERY markup and placeholder pagination. Definitive Methods tables and figures refer to 2020dasgupta-j-chem-phys-reaxff-molecular.

Summary

ReaxFF molecular dynamics of alkali chloride salts in water at 700 K maps structure and dynamics across liquid-like to vapor-like densities, reporting RDFs/ADFs, ion diffusion, H-bond residence times, Voronoi voids, and clustering. This slug is a proof duplicate; scientific intent matches 2020dasgupta-j-chem-phys-reaxff-molecular. Supercritical aqueous electrolytes matter for geochemistry, hydrothermal synthesis, and extreme process windows; the JCP study emphasizes how dielectric screening and void topology change when water density drops far below ambient liquid values.

Methods

  • Potential: ReaxFF for water and alkali/halide interactions as cited in the article.
  • Integration: Velocity Verlet, timestep 0.25 fs; Berendsen thermostat, 100 fs damping on the full system (per Methods).
  • State points: 700 K at water densities ρ = 1.00, 0.70, 0.35, and 0.15 g cm\(^{-3}\) for each salt (Table I on the canonical page); salts LiCl, NaCl, KCl, RbCl, CsCl as reported.
  • Ion clustering diagnostics complement RDFs so contact ion-pair populations can be tracked as screening weakens.
  • MD (same science as VOR, see 2020dasgupta-j-chem-phys-reaxff-molecular): ReaxFF molecular dynamics; atom-resolved periodic supercells for each alkali chloride + water composition with water densities ρ = 1.00, 0.70, 0.35, and 0.15 g cm⁻³ in Table I on the canonical page; 700 K; Berendsen thermostat, 0.25 fs timestep, 100 fs Berendsen damping. Equilibration/production lengths in ps/ns: see VOR (N/A to duplicate the full table in this proof note). Barostat: N/A for isochoric state-point grids. Pressure control: N/A in those NVT production segments. Electric field: N/A. Enhanced sampling: N/A.

Findings

  • Coordination, diffusion, void statistics, and clustering trends with density and ion identity are summarized on 2020dasgupta-j-chem-phys-reaxff-molecular—including larger void volumes and altered transport at low density, and salt clusters when dielectric screening weakens.
  • Readers should lift quantitative diffusion coefficients and uncertainty estimates from the VOR article text rather than from query overlay pages in the proof PDF.

Limitations

Proof PDFs are not substitutes for the version of record; figures and line numbers may differ. 700 K and supercritical conditions are outside ambient electrolyte regimes.

Curation note: the local file includes AIP author query markup—open 2020dasgupta-j-chem-phys-reaxff-molecular for clean Methods tables when building Phase 5 chunks or benchmark cards. Supercritical density sweeps are the distinguishing feature versus ambient Fedkin validation papers. Alkali series Li→Cs trends should be read alongside void percolation discussion on the canonical JCP page. Berendsen thermostat damping 100 fs matches the canonical Methods paragraph for these state points.

Relevance to group

van Duin-group ReaxFF on supercritical aqueous electrolytes; this entry records galley bytes only.

Citations and evidence anchors

Reader notes (navigation)