- Open Access
Origins and predictability of the hydrostatic limit of molecular liquids
Phys. Rev. E 114, 035433 – Published 25 September, 2026
DOI: https://doi.org/10.1103/f2k4-hf7d
Abstract
Loss of hydrostaticity limits high-pressure experiments, as pressure transmitting media solidify under compression. Here, we report a strong and positive correlation between the increase of molar density with pressure () and the hydrostatic limit (HL) associated with the vitrification of isothermally compressed molecular liquids. This correlation is derived using molecular dynamics simulations and is validated against experimental values of and HL. The positive –HL correlation can be rationalized by writing as a function of the molar density () and the pressure-induced decrease in molar volume (): . While liquids are seen to not exhibit large and simultaneously, we find that large HL values originate mostly from large , or, to some extent, from a large . At the molecular level, large and large are linked to small molecular sizes and to low characteristic frequencies of intermolecular vibrations (), respectively.
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References (111)
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