Open questions on defining and computing the vapour-liquid surface tension by virial and test transformation approaches

Martin Thomas Horsch

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arXiv · 2501.12755

Open questions on defining and computing the vapour-liquid surface tension by virial and test transformation approaches

Martin Thomas Horsch

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Abstract

This work addresses four problems in defining and computing the surface tension of vapour-liquid interfaces: (1) The apparent kinetic contribution to the surface tension, and what it is that makes it appear; (2) the problem of defining the local virial, which for some purposes appears to be necessary; (3) the disagreement between results for spherical interfaces when using different methods, specifically the virial and the test area method; (4) how the surface tension values obtained from these methods can be related to the definition of the surface tension from thermodynamics - since if they cannot, it is a meaningless exercise to compute them. At the end, all these problems remain unsolved: They are "open questions."

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Martin Thomas Horsch. 2025-01-22. Open questions on defining and computing the vapour-liquid surface tension by virial and test transformation approaches. https://arxiv.org/abs/2501.12755

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