Abstract
High-resolution ac calorimetry was used to measure the heat capacity of n-hexyl-4-n-pentyloxybiphenyl-4-carboxylate in the vicinity of the smectic-A (SmA)hexatic-B and hexatic-B-E transitions. The SmA hexatic-B transition was found to be continuous with critical exponents -=+=0.610.02 and amplitude ratio A+A-=0.840.03. The addition of a crystalline-B material [N-(4-n- butyloxybenzylidene)-4-octylaniline (4O.8), 10 wt.%] produced a weakly-first-order SmA hexatic-B phase transition. The data with | T-Tc |100 mK can be fitted by a power law with =0.490.02 and A+A-=0.820.03. The large values for the critical exponents and the theoretical suggestion that the Sm Ahexatic-B transition may be near tricritical point (t=0.5) are discussed. The hexatic-B-E transition was found to be first order in nature.
Original language | English (US) |
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Pages (from-to) | 2433-2441 |
Number of pages | 9 |
Journal | Physical Review A |
Volume | 28 |
Issue number | 4 |
DOIs | |
State | Published - 1983 |
Bibliographical note
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