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Published on: May 27, 2020
Reduced dimensionality in organic electro-optic materials: theory and defined order.
Stephanie J Benight1, Lewis E Johnson, Robin Barnes
1Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
The Journal of Physical Chemistry. B
|August 25, 2010
Summary
Electronic interactions in coumarin-containing macromolecules significantly improve poling-induced order. This study reveals how lattice symmetry effects enhance acentric order in organic electro-optics materials.
Area of Science:
- Organic electro-optics
- Materials science
- Soft condensed matter physics
Background:
- Advancing organic electro-optics requires identifying interactions that enhance poling-induced order.
- Coumarin pendant groups in macromolecules offer potential for such interactions.
Purpose of the Study:
- To demonstrate enhanced acentric order in chromophore-containing macromolecules using coumarin interactions.
- To explain the role of lattice-symmetry effects in altering the relationship between centrosymmetric and acentric order.
- To define lattice dimensionality through the interplay of centrosymmetric and acentric order.
Main Methods:
- Experimentally, acentric order was measured using attenuated total reflection and hyper-Rayleigh scattering.
- Centrosymmetric order was determined via variable angle polarization referenced absorption spectroscopy.
- Theoretically, order was predicted using statistical mechanical models for soft condensed matter.
Main Results:
- Demonstrated significant enhancement of poling-induced order through coumarin pendant group interactions.
- Explained acentric order enhancement via lattice-symmetry effects constraining orientational degrees of freedom.
- Established a method to define lattice dimensionality based on the ratio of centrosymmetric to acentric order.
Conclusions:
- Electronic intermolecular electrostatic interactions, specifically in coumarin-containing macromolecules, can significantly improve poling-induced order.
- Lattice-symmetry effects play a crucial role in enhancing acentric order by altering orientational freedom.
- The relationship between centrosymmetric and acentric order provides a means to define lattice dimensionality in these materials.
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