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Updated: Feb 27, 2026
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Ferroelectric Polarization and Second Harmonic Generation in Supramolecular Cocrystals with Two Axes of
Ashwin Narayanan, Dennis Cao, Laszlo Frazer
1Department of Medicine and Simpson-Querrey Institute for BioNanotechnology, Northwestern University , Chicago, Illinois 60611, United States.
Abstract:
Ferroelectricity in organic materials remains a subject of great interest, given its potential impact as lightweight information storage media. Here we report supramolecular charge-transfer cocrystals formed by electron acceptor and donor molecules that exhibit ferroelectric behavior along two distinct crystallographic axes. The solid-state superstructure of the cocrystals reveals that a 2:1 ratio of acceptor to donor molecules assemble into nearly orthogonal mixed stacks in which the molecules are positioned for charge-transfer in face-to-face and edge-to-face orientations, held together by an extended hydrogen-bonding network. Polarization hysteresis was observed along the face-to-face and edge-to-face axes at room temperature. The noncentrosymmetric nature of the cocrystals, required to observe ferroelectric behavior, is demonstrated using second harmonic generation measurements. This finding suggests the possibility of designing supramolecular arrays in which organic molecules support multidimensional information storage.
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