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arXiv · 1809.10014

On the Diffuse Structure of the Toluene - Water Interface

Aleksey M. Tikhonov
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Abstract

The electric density profile along the normal to the phase interface between aromatic hydrocarbon toluene and water has been studied by X-ray reflectometry using synchrotron radiation. According to the experimental data, the width of the interface under normal conditions is (5.7 +/- 0.2) Angstrom. This value is much larger than a theoretical value of (3.9 +/- 0.1) Angstrom predicted by the theory of capillary waves with an interphase tension of (36.0 +/- 0.1) mN/m. The observed broadening of the interface is attributed to its own diffuse near-surface structure with a width no less than 4 Angstroms, which is about the value previously discussed for high-molecular-weight n-alkane - water and 1,2-dichloroethane - water interfaces.

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Aleksey M. Tikhonov. 2018-09-26. On the Diffuse Structure of the Toluene - Water Interface. https://doi.org/10.1134/s0021364018140126

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