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Observation of surface layering in a nonmetallic liquid

Haiding Mo·Guennadi Evmenenko·Sumit Kewalramani·Kyungil Kim·Steven N. Ehrlich·Pulak Dutta
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Abstract

Oscillatory density profiles (layers) have previously been observed at the free surfaces of liquid metals, but not in other isotropic liquids. We have used x-ray reflectivity to study a molecular liquid, tetrakis(2-ethylhexoxy)silane. When cooled to T/Tc~0.25 (well above the freezing point for this liquid), density oscillations appear at the surface. Lateral order within the layers is liquid-like. Our results confirm theoretical predictions that a surface-layered state will appear even in dielectric liquids at sufficiently low temperatures, if not preempted by freezing.

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Haiding Mo, Guennadi Evmenenko, Sumit Kewalramani, Kyungil Kim, Steven N. Ehrlich, Pulak Dutta. 2006-02-17. Observation of surface layering in a nonmetallic liquid. https://doi.org/10.1103/physrevlett.96.096107

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