Eur. Phys. J. E (2005) 16: 361-364
https://doi.org/10.1140/epje/i2004-10091-3

Characterization of the smectic-A-hexatic-B transition in 65OBC by adiabatic scanning calorimetry

Laboratorium voor Akoestiek en Thermische Fysica, Departement Natuurkunde en Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001, Leuven, Belgium

^* e-mail: Bert.VanRoie@fys.kuleuven.ac.be

Received: 5 October 2004
Accepted: 14 January 2005
Published online: 7 February 2005

Abstract

We investigated the smectic-A-hexatic-B (SmA-HexB) transition in the liquid-crystal n-hexyl-4’-n-pentyloxybiphenyl-4-carboxilate (65OBC) with adiabatic scanning calorimetry. We were able to prove in a direct way that this transition is indeed very weakly first order, as was already suggested in the literature. The latent heat at the transition was determined to be ΔH _L = 0.04±0.02 J/g. Our experiments confirm the high value for the heat capacity critical exponent earlier reported, yielding α = 0.64±0.05.