Document Type
Article
Publication Date
8-1-1998
Abstract
Magnetically induced Freedericksz measurements were performed in the nematic liquid crystal phase to extract the elastic constants of a terminal-lateral-lateral-terminal trimer, i.e., a trimer in which the connections to the first and third mesogens are at the end of the mesogen and both attachments to the central mesogen are lateral. Polymeric liquid crystals based on this unit have negative Poisson ratios. Additionally, electric field Kerr measurements were performed in the isotropic phase to extract the orientational susceptibility. The elastic constants were found to be similar to values obtained for typical monomers, albeit with a slightly enhanced ratio K33/K11 and reduced ratio K11/K22, especially near the transition temperature. The temperature dependence of the susceptibility was found to deviate significantly from that of typical monomers. The observed behavior is discussed in terms of coupled order parameters representing the terminal and core mesogens of the molecule.
Publication Title
Physical Review E
Rights
Copyright 1998 by the American Physical Society.
Recommended Citation
Orientational Susceptibility and Elastic Constants Near the Nematic-Isotropic Phase Transition for Trimers with Terminal-Lateral-Lateral-Terminal Connections. Kang D., Mahajan M.P., Petschek R.G., Rosenblatt C., He C., Liu P., Griffin A.C., Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics 58:2 SUPPL. B, 2041-2046 (1998).