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Observation of the Smectic C -- Smectic I Critical Point

S. Krishna Prasad·D. S. Shankar Rao·S. Chandrasekhar·M. E. Neubert·J. W. Goodby
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Abstract

We report the first observation of the smectic C--smectic I (C--I) critical point by Xray diffraction studies on a binary system. This is in confirmity with the theoretical idea of Nelson and Halperin that coupling to the molecular tilt should induce hexatic order even in the C phase and as such both C and I (a tilted hexatic phase) should have the same symmetry. The results provide evidence in support of the recent theory of Defontaines and Prost proposing a new universality class for critical points in layered systems.

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S. Krishna Prasad, D. S. Shankar Rao, S. Chandrasekhar, M. E. Neubert, J. W. Goodby. 1994-11-18. Observation of the Smectic C -- Smectic I Critical Point. https://doi.org/10.1103/physrevlett.74.270

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