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arXiv · 2602.02504

Single-run determination of the saturation vapor pressure and enthalpy of vaporization/sublimation of a substance undergoing successive solid-solid and solid-liquid phase transitions: the case of $N$-methyl acetamide

Mohsen Salimi·Aurelien Dantan·Henrik B. Pedersen
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Abstract

We report on the dynamical measurement of the saturation vapor pressure of $N$-methyl acetamide in the temperature range $-30^\circ$C to $34^\circ$C. This is achieved by monitoring the pressure inside a vacuum chamber in which a precooled sample of the substance slowly thermalizes to the chamber temperature, undergoing first a phase transition between two crystalline structures around $1^\circ$C and then a solid-liquid phase transition around $30^\circ$C. Such a measurement provides in a single run accurate data for the saturation vapor pressure and the enthalpies of sublimation and vaporization of the different phases of the investigated substance.

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Mohsen Salimi, Aurelien Dantan, Henrik B. Pedersen. 2026-01-21. Single-run determination of the saturation vapor pressure and enthalpy of vaporization/sublimation of a substance undergoing successive solid-solid and solid-liquid phase transitions: the case of $N$-methyl acetamide. https://doi.org/10.1016/j.molliq.2026.129680

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