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A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
The equilibrium structure of lithium salt solutions in ether-functionalized ammonium ionic liquids
Pedro Henrique Figueiredo1, Leonardo J A Siqueira, Mauro C C Ribeiro
1Laboratório de Materiais Híbridos, Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Rua São Nicolau 210, CEP 09913-030, Diadema, SP, Brazil.
The Journal of Physical Chemistry. B
|September 18, 2012
Summary
Adding lithium ions to ionic liquids alters their structure. Lithium ions strongly coordinate with anions, affecting charge ordering and creating non-uniform cation distributions, enhancing interactions between ammonium cations.
Area of Science:
- Physical Chemistry
- Materials Science
Background:
- Ionic liquids (ILs) are salts that are liquid at ambient temperatures.
- Bis(trifluoromethylsulfonyl)imide ([Tf(2)N](-)) is a common anion in ILs.
- Ether-functionalized ammonium cations are used in ILs.
Purpose of the Study:
- To investigate structural changes in ionic liquids upon addition of lithium ions.
- To understand the effect of lithium on charge ordering and intermediate range order.
- To analyze how lithium influences cation-cation interactions in ether-functionalized ammonium-based ILs.
Main Methods:
- Molecular dynamics simulations were employed.
- Static structure factors were calculated.
- Ternary mixtures of lithium, ammonium cations, and [Tf(2)N](-) anion were simulated.
Main Results:
- Lithium ions significantly modify charge ordering due to strong coordination with [Tf(2)N](-).
- Intermediate range order, observed in neat ILs, is altered by lithium addition.
- Lithium solutions exhibit non-uniform Li(+) cation distribution.
- Li(+) enhances interactions between ammonium cations via ether chain oxygen-nitrogen correlations.
Conclusions:
- Lithium incorporation disrupts the inherent structure of neat ionic liquids.
- The strong Li(+)-[Tf(2)N](-) interaction dictates structural modifications.
- Enhanced ammonium-ammonium interactions are a key consequence of lithium presence.
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