1. Open Access Kent State
  2. Diffuse Cone Behavior and Microscopic Structure of the de Vries Smectic-A and Sm-C Phases
Author(s)
Abstract

Direct synchrotron x-ray scattering measurements of the orientational order parameter, S, corresponding to the siloxane and hydrocarbon parts of the molecule, smectic layer spacing, and director tilt angle with respect to the smectic-C (SmC) layer normal in the de Vries smectics-A (SmA) and SmC phases of two organosiloxane mesogens are reported. The results reveal that (i) the SmC (tilt) order parameter exponent β = 0.26 ± 0.01 for 2nd order SmA-SmC transition in excellent agreement with the tricritical behavior, (ii) the siloxane and hydrocarbon parts of the molecules are segregated and oriented parallel to the director with different degree of orientational order, and (iii) thermal evolution of the effective molecular length is different in the two phases contrary to the conventional wisdom.
Format
Article
Identifier(s)
10.1117/12.893045
Publication Date
2011-01-01
Publication Title
Proceedings of the SPIE
Volume
8114
First Page
811400
Subject
Community
Department of Physics
Comments

Copyright 2011, Society of Photo-Optical Instrumentation Engineers.
Permalink https://oaks.kent.edu/phypubs/99
Yoon, H., Agra-Kooijman, D., Ayub, K., Lemieux, R., & Kumar, S. (2011). Diffuse Cone Behavior and Microscopic Structure of the de Vries Smectic-A and Sm-C Phases. Proceedings of the SPIE. https://doi.org/10.1117/12.893045
Yoon, Hyung, Dena Agra-Kooijman, Khurshid Ayub, Robert Lemieux, and Satyendra Kumar. 2011. “Diffuse Cone Behavior and Microscopic Structure of the De Vries Smectic-A and Sm-C Phases”. Proceedings of the SPIE. https://doi.org/10.1117/12.893045.
Yoon, H., D. Agra-Kooijman, K. Ayub, R. Lemieux, and S. Kumar. Diffuse Cone Behavior and Microscopic Structure of the De Vries Smectic-A and Sm-C Phases. Proceedings of the SPIE, 1 Jan. 2011, doi:10.1117/12.893045.