# Absolute Measurement of the Critical Properties of Second Sound at the Smectic-A-to-Nematic Phase Transition in 8OCB

 Title: Absolute Measurement of the Critical Properties of Second Sound at the Smectic-A-to-Nematic Phase Transition in 8OCB Author: Pershan, Peter S.; Fisch, M. R.; Sorensen, L. B. Note: Order does not necessarily reflect citation order of authors. Citation: Fisch, M. R., L. B. Sorensen, and Peter S. Pershan. 1981. Absolute measurement of the critical properties of second sound at the smectic-A-to-nematic phase transition in 8OCB. Physical Review Letters 47(1): 43–46. Full Text & Related Files: Fisch_Absolute.pdf (639.5Kb; PDF) Abstract: Light scattered from the driven free surface of the smectic-A phase of octyloxy cyanobiphenyl (8OCB) provides a low-frequency measurement of second sound. This yields an absolute measurement of the smectic elastic constant, B. There is no dispersion in either the angular or frequency dependence of B for angles $$35^{\circ}-83^{\circ}$$ from the normal and for frequencies from 10-100 kHz. Near the smectic-A-to-nematic phase transition the smectic elastic constant can be described by $$B=(6.03 \pm 0.05) \times 10^7 (T_{NA}-T)^{0.32 \pm 0.015} dyn/cm^2$$. Published Version: doi:10.1103/PhysRevLett.47.43 Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:10361977 Downloads of this work: