2021/03/12 by Graeme J. Ackland, Hongxiang Zong, Victor Naden Robinson +3 · 8 citations
Chemical Engineering · Chemistry · Mathematics · Physics and Astronomy · #Advanced Chemical Physics Studies #Advanced Physical and Chemical Molecular Interactions #Alkali metal #Chemistry #Geometry #Ionic liquids properties and applications #Line (geometry) #Materials science #Mathematics #Melting curve analysis #Phase transition #Physics #Thermodynamics #Volume (thermodynamics) #cond-mat.other #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevb.104.054120
published in Physical review. B./Physical review. B 104(5) (American Physical Society)
arxiv created 2021/03/12 · openalex created_date 2021/03/29 · openalex publication_date 2021/08/30 · arxiv updated 2021/09/08 · openalex updated_date 2026/08/05
We present a thermodynamic model which explains the presence of a negative slope in the melt curve, as observed in systems as diverse as the alkali metals and molecular hydrogen at high pressure. We assume that components of the system can be in one of two well defined states---one associated with low energy, the other with low volume. The model exhibits a number of measurable features which are also observed in these systems and are therefore expected to be associated with all negative Clapeyron-slope systems: first order phase transitions and thermodynamic anomalies along Widom lines. The melt curve maximum is a feature of the model, but appears well below the pressures where the change in state occurs in the solid: the solid-solid transition is related to the melt line minimum. An example of the model fitted to the electride transition in potassium is discussed.