Molecular dynamics simulations of highly concentrated salt solutions

Structural and transport effects in polymer electrolytes

M. Forsyth, V. A. Payne, Mark A Ratner, S. W. de Leeuw, D. F. Shriver

Research output: Contribution to journalArticle

48 Citations (Scopus)

Abstract

Structural, thermodynamic and transport properties have been calculated in concentrated non-aqueous NaI solutions using molecular dynamics simulations. Although the solvent has been represented by a simplistic Stockmayer fluid (spherical particles with point dipoles), the general trends observed are still a useful indication of the behavior of real non-aqueous electrolyte systems. Results indicate that in low dielectric media, significant ion pairing and clustering occurs. Contact ion pairs become more prominent at higher temperatures, independent of the dielectric strength of the solvent. Thermodynamic analysis shows that this temperature behavior is predominantly entropically driven. Calculation of ionic diffusivities and conductivities in the NaI/ether system confirms the clustered nature of the salt, with the conductivities significantly lower than those predicted from the Nernst-Einstein relation. In systems where the solvent-ion interactions increase relative to ion-ion interactions (lower charge or higher solvent dipole moment), less clustering is observed and the transport properties indicate independent motion of the ions, with higher calculated conductivities. The solvent in this system is the most mobile species, in comparison with the polymer electrolytes where the solvent is practically immobile.

Original languageEnglish
Pages (from-to)1011-1026
Number of pages16
JournalSolid State Ionics
Volume53-56
Issue numberPART 2
DOIs
Publication statusPublished - 1992

Fingerprint

Electrolytes
Molecular dynamics
Polymers
Salts
electrolytes
Ions
molecular dynamics
salts
Computer simulation
polymers
ions
simulation
Transport properties
transport properties
nonaqueous electrolytes
conductivity
low conductivity
Dipole moment
Ether
diffusivity

ASJC Scopus subject areas

  • Electrochemistry
  • Physical and Theoretical Chemistry
  • Energy Engineering and Power Technology
  • Materials Chemistry
  • Condensed Matter Physics

Cite this

Molecular dynamics simulations of highly concentrated salt solutions : Structural and transport effects in polymer electrolytes. / Forsyth, M.; Payne, V. A.; Ratner, Mark A; de Leeuw, S. W.; Shriver, D. F.

In: Solid State Ionics, Vol. 53-56, No. PART 2, 1992, p. 1011-1026.

Research output: Contribution to journalArticle

Forsyth, M. ; Payne, V. A. ; Ratner, Mark A ; de Leeuw, S. W. ; Shriver, D. F. / Molecular dynamics simulations of highly concentrated salt solutions : Structural and transport effects in polymer electrolytes. In: Solid State Ionics. 1992 ; Vol. 53-56, No. PART 2. pp. 1011-1026.
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