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Electrofreezing of Liquid Ammonia.

ABSTRACT: Here we prove that, in addition to temperature and pressure, another important thermodynamic variable permits the exploration of the phase diagram of ammonia: the electric field. By means of (path integral) ab initio molecular dynamics simulations, we predict that, upon applying intense electric fields on ammonia, the electrofreezing phenomenon occurs, leading the liquid toward a novel ferroelectric solid phase. This study proves that electric fields can generally be exploited as the access key to otherwise-unreachable regions in phase diagrams, unveiling the existence of new condensed-phase structures. Furthermore, the reported findings have manifold practical implications, from the safe storage and transportation of ammonia to the understanding of the solid structures this compound forms in planetary contexts.

SUBMITTER: Cassone G

PROVIDER: S-EPMC9619927 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Electrofreezing of Liquid Ammonia.

Cassone Giuseppe G Sponer Jiri J Sponer Judit E JE Saija Franz F

The journal of physical chemistry letters 20221018 42

Here we prove that, in addition to temperature and pressure, another important thermodynamic variable permits the exploration of the phase diagram of ammonia: the electric field. By means of (path integral) <i>ab initio</i> molecular dynamics simulations, we predict that, upon applying intense electric fields on ammonia, the electrofreezing phenomenon occurs, leading the liquid toward a novel ferroelectric solid phase. This study proves that electric fields can generally be exploited as the acce ...[more]

PMID: 36255376

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