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CPP: Chemische Physik und Polymerphysik
CPP 19: Dynamics I
CPP 19.2: Talk
Tuesday, March 8, 2005, 10:00–10:15, TU C230
Intrastack rotation in pyrene hexafluoroarsenate — •S. Matejcek and E. Dormann — Physikalisches Institut, Universität Karlsruhe (TH), D-76128 Karlsruhe, Germany
The specific heat of the quasi-one dimensional organic conductor pyrene hexafluoroarsenate ((Py)7(Py)4(AsF6)4·4CH2Cl2) was measured between 10 K and 250 K using the method of continuous heating. The contribution of the lattice to the specific heat was modelled using the Debye-model and Einstein terms. The variation of the specific heat at the structural phase transition that is accompanied by 60∘ rotation of one of the stacked pyrene molecules could well be reproduced using a cooperation model including the formation of domains, and the surprisingly high transition entropy was explained qualitatively.