Transient spectroscopy of 80K second order phase transition in k-(BEDT-TTF)2Cu[N(CN)2]X (X= Cl, I, and Br)

M. A. Tanatar; T. Ishiguro; N. D. Kushch; E. B. Yagubskii

M. A. Tanatar Інститут хімії поверхні НАН України
T. Ishiguro Japan Science and Technology Corporation
N. D. Kushch Institute of Problems of Chemical Physics
E. B. Yagubskii Institute of Problems of Chemical Physics

Анотація

Second order phase transition, observed previously in the title salts in thermal expansion studies close to 80 K, was studied in insulating X= Cl and I salts by a transient spectroscopy of structural relaxation and by controlled annealing. A notable difference in the activation energy of transformation and in annealing behavior compared to the metallic X= Br salt was found, showing transformation towards different structural states at low temperature.

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