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Updated: Mar 21, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Isotropic rotation vs. shear relaxation in supercooled liquids with globular cage molecules
Derrick C Kaseman1, Ozgur Gulbiten2, Bruce G Aitken2
1Division of Materials Science, University of California at Davis, Davis, California 95616, USA.
Abstract:
The temperature dependence of the rotational dynamics of P4Se3 molecules in the glass-forming molecular liquid P5Se3 is studied using two-dimensional (31)P nuclear magnetic resonance spectroscopy. Unlike typical molecular glass-forming liquids, the constituent molecules in the P5Se3 liquid perform rapid isotropic rotation without significant translational diffusion in the supercooled regime and this rotational process shows a decoupling in time scale from shear relaxation by nearly six orders of magnitude at the glass transition. This dynamical behavior of liquid-like rotation and localized translation appears to be universal to glass-forming liquids with high-symmetry globular molecules that are characterized by an underlying thermodynamically stable plastic crystal phase.
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