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Quantum-Chemical and Molecular Dynamics Investigations of Magnesium Chloride Complexes in Dimethoxyethane Solutions.

ABSTRACT: Quantum-chemical calculations and classical and ab initio molecular dynamics simulations have been performed to study the Mg²⁺-conducting electrolytes based on Mg(TFSI)₂/MgCl₂ solutions in dimethoxyethane. It has been shown that depending on the TFSI/Cl^- ratio, the Mg₂Cl₂ ²⁺ or Mg₃Cl₄ ²⁺ complexes are preferred as stable ion aggregates. In the initial stages of the ion association process, MgCl⁺, MgCl₂, and Mg₂Cl₃ ⁺ are formed as intermediate species. Calculations of harmonic frequencies and simulations of the IR spectrum of the electrolyte from the ab initio MD trajectories have been used to identify the spectral range of vibrations of ion aggregates found in the modeled electrolyte. The results have been discussed in the context of experimental data.

SUBMITTER: Wrobel P

PROVIDER: S-EPMC7288557 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Quantum-Chemical and Molecular Dynamics Investigations of Magnesium Chloride Complexes in Dimethoxyethane Solutions.

Wróbel Piotr P Kubisiak Piotr P Eilmes Andrzej A

ACS omega 20200526 22

Quantum-chemical calculations and classical and ab initio molecular dynamics simulations have been performed to study the Mg2+-conducting electrolytes based on Mg(TFSI)2/MgCl2 solutions in dimethoxyethane. It has been shown that depending on the TFSI/Cl- ratio, the Mg2Cl2 2+ or Mg3Cl4 2+ complexes are preferred as stable ion aggregates. In the initial stages of the ion association proces ...[more]

PMID: 32548468

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