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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Long-range orientation correlation in liquids.
1Department of Physics and Astronomy, University of Nevada, Las Vegas, Nevada 89154-4002, USA. shelton@physics.unlv.edu
The Journal of Chemical Physics
|February 4, 2012
Summary
Molecular orientation correlations in liquids are longer-range than previously assumed. Second harmonic light scattering experiments reveal these long-range correlations, challenging existing models of liquid structure.
Area of Science:
- Condensed matter physics
- Physical chemistry
- Molecular dynamics
Background:
- Intermolecular interactions in liquids typically lead to short-range correlations.
- Previous assumptions limited these correlations to a few molecular diameters.
- The structure of isotropic liquids is fundamental to many chemical and physical processes.
Purpose of the Study:
- To investigate the extent of molecular orientation correlations in isotropic liquids.
- To challenge the prevailing assumption of short-range correlations.
- To provide new insights into the molecular structure of liquids.
Main Methods:
- Second harmonic light scattering experiments were employed.
- The polarization dependence of scattered light was measured.
- Observations were interpreted using polar collective modes and explicit models.
Main Results:
- Long-range orientation correlations were observed in several isotropic liquids, including water.
- This contradicts the widely held assumption of short-range correlations.
- The findings are consistent with theoretical models of collective modes.
Conclusions:
- The structure of molecular liquids is more complex than previously understood.
- Long-range orientation correlations play a significant role in liquid behavior.
- These results offer a new benchmark for validating computational simulations of liquids.
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