Thermodynamics of Li+–Crown Ether Interactions in Aqueous Solvent

05 January 2023, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Lithium ion-based batteries are ubiquitous in modern technology due to applications in personal electronics and high-capacity storage for electric vehicles. Concerns about lithium supply and battery waste have prompted interest in lithium recycling methods. The crown ether, 12-crown-4, has been studied for its abilities to form stable complexes with lithium ions (\ce{Li+}). In this paper, molecular dynamics simulations are applied to examine the binding properties of a 12-crown-4—\ce{Li+} system in aqueous solution. It was found that 12-crown-4 did not form stable complexes with \ce{Li+} in aqueous solution due to the binding geometry which was prone to interference by surrounding water molecules. In addition, the binding properties of sodium ions (\ce{Na+}) to 12-crown-4 are examined for comparison. Subsequently, calculations were performed with the crown ethers 15-crown-5 and 18-crown-6 to study their complexation with \ce{Li+} as well. It was determined that binding was unfavorable for both types of ions for all three crown ethers tested, though 15-crown-5 and 18-crown-6 showed a marginally greater affinity for \ce{Li+} than 12-crown-4. Metastable minima present in the potential of mean force for \ce{Na+} render binding marginally more likely there. We discuss these results in the context of membrane based applications of crown ethers for \ce{Li+} separations.


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.