Lithium ion solvation and diffusion in bulk organic electrolytes from first-principles and classical reactive molecular dynamics

Evidence and attribution¶

Authority of statements

Summaries follow the J. Phys. Chem. B article (doi). The corpus file is an author proof dated 2014; publication is 2015—front matter matches the journal.

Summary¶

First-principles MD of Li⁺ and PF₆⁻ in bulk ethylene carbonate (EC), ethyl methyl carbonate (EMC), and EC/EMC mixtures with LiPF₆. Li⁺ coordinates to carbonyl and/or ether oxygens (and sometimes PF₆⁻) with a broadly tetrahedral first shell whose composition depends on solvent. Diffusion coefficients are larger in EMC than EC, correlating with weaker Li⁺ solvation; PF₆⁻ diffuses faster with a looser solvation shell. The work is paired in the title with classical reactive MD analysis in the full paper (see Methods therein). Together, the AIMD and ReaxFF strands aim to connect atomistic solvation structure to continuum-relevant transport trends for carbonate electrolytes.

Methods¶

First-principles MD (bulk carbonate electrolytes)¶

FPMD/DFT simulations treat LiPF₆ dissolved in bulk ethylene carbonate (EC), ethyl methyl carbonate (EMC), and EC/EMC mixtures to resolve Li⁺ and PF₆⁻ solvation and diffusion statistics (Summary; LLNL–Penn State collaboration).

Classical reactive MD (paired in the article title)¶

The manuscript’s classical reactive MD strand uses ReaxFF (details in JPCB Methods) to reach larger systems/longer times than AIMD, with explicit comparison targets enumerated in the article (Summary).

Proof vs version-of-record¶

Local pdf_path is an ACS author proof; publication metadata in front matter reflects J. Phys. Chem. B 119, 1535–1545 (2015). Prefer the VOR PDF for pagination and figure labels.

Extract anchor¶

Abstract-level pointers: normalized/extracts/2014ong-venue-research_p1-2.txt plus papers/Ong_JPCB_IL_DFT_ReaxFF_2014_proof.pdf (ACS author proof; published article J. Phys. Chem. B 119, 1535–1545, 2015).

1 — MD application (atomistic dynamics)¶

First-principles MD: DFT-based (FPMD) trajectories treat bulk LiPF₆ in EC, EMC, and EC/EMC mixtures (Summary; full kinetics in JPCB).
Classical reactive MD: ReaxFF strand paired in the title for larger systems/longer times than AIMD (Summary); N/A — integrator, timestep, thermostat, equilibration/production ns, and thermostat labels not reproduced here—read the Methods section of the published PDF.
Engine / code: N/A — software not named in the short wiki summary layer.
System size & composition: N/A — atom totals not copied into this page from the proof/extract.
Boundaries / periodicity: Bulk liquid electrolyte cells imply PBC in standard practice, but N/A — explicit boundary wording not checked on this slug—confirm in JPCB.
Ensemble: NVT/NPT choices for AIMD vs ReaxFF segments are N/A — not stated on this page; see article.
Temperature: 30 °C appears in the wiki’s abstract-derived discussion of experimental diffusion ranges used for context (extract-backed summary on file).
Pressure: N/A — not emphasized in the indexed abstract layer summarized here.
Electric field: N/A — not stated in the excerpted discussion used here.
Replica / enhanced sampling: N/A — not stated here.

2 — Force-field training¶

N/A — this page is an application note; any ReaxFF parameter updates belong to the JPCB Methods/SI, not this summary.

3 — Static QM / DFT-only (AIMD block)¶

Functional, dispersion, basis, k-sampling, and production lengths for FPMD are defined in J. Phys. Chem. B 119, 1535–1545—N/A — not duplicated on this wiki stub.

Findings¶

Outcomes and mechanisms¶

Li⁺ coordinates through carbonyl and/or ether oxygens (sometimes PF₆⁻ participates), with a broadly tetrahedral first shell whose composition depends on solvent (abstract).

Comparisons¶

Li⁺ diffusion coefficients are slightly larger in EMC than EC, correlating with weaker Li⁺ solvation; PF₆⁻ diffuses faster with a weakly bound, poorly defined first shell (abstract). Experimental diffusion ranges cited for context include order ~(1–8)×10⁻⁶ cm² s⁻¹ for Li⁺ at 30 °C and ~(1.5–4.5)×10⁻⁶ cm² s⁻¹ for mixed EC/EMC depending on salt concentration (discussion text present in the corpus extract file referenced above).

Sensitivity and outlook¶

Solvent identity (EC vs EMC vs mixtures) modulates solvation strength and inferred transport trends in the abstract framing; the manuscript positions these results as input to parameterizing/validating larger-scale reactive models.

Corpus honesty¶

Local pdf_path is an ACS author proof; cite pagination/figures from the version-of-record JPCB PDF when possible (2014ong-venue-research maintainer note links NON_PRIMARY_ARTICLE_PAPER_SLUGS.md).

Limitations¶

Bulk liquid focus (not full SEI chemistry); proof PDF; DFT/FF costs limit duration and system composition sweep.

Relevance to group¶

Core LLNL–Penn State electrolyte collaboration including van Duin; central to battery electrolyte narrative in the corpus.

Citations and evidence anchors¶

https://doi.org/10.1021/jp508184f — J. Phys. Chem. B 119, 1535–1545 (2015).

Corpus pdf_path is an ACS author proof; the published article is J. Phys. Chem. B 119, 1535–1545 (2015). Maintainer catalog: Non-primary article PDF slugs (GitHub) (section D, 2014ong-venue-research).