Abstract
The heat capacity of a single crystal of the two dimensional antiferroelectric squaric acid was measured particularly near the phase transition. In a wide temperature range belowT c a strong temperature dependence of the anomaleous specific heat is found which can be described by a critical exponentα′=0.5. The behaviour close toT c is determined by a latent heat thus indicating the phase transition to be of the first order. Near the phase transition the thermal behaviour can be described by a Landau type theory. The smallness of the transition entropy detected may be ascribed possibly to proton tunneling.
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Barth, E., Helwig, J., Maier, H.D. et al. Specific heat of the two dimensional antiferroelectric squaric acid. Z Physik B 34, 393–397 (1979). https://doi.org/10.1007/BF01325204
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DOI: https://doi.org/10.1007/BF01325204