Far infrared response of α- and αt-(BEDT-TTF)2I3
نویسندگان
چکیده
2014 The temperature dependence of the reflectivity of 03B1and 03B1t-(BEDT-TTF)2I3 was determined in the 10-700 cm-1 range. Moreover the transmission spectra of 03B1-phase between 10 and 33 cm-1 were studied. Using Kramers-Kronig analysis the IR conductivity and permittivity were calculated. The similarity of 03B1t and 03B2-phases was confirmed. The spectra in the metallic phase are dominated by a broad electronic peak between 200 and 500 cm-1 which can be understood as due to transitions across the small gap whose origin is discussed. In the spectra a rich phonon peak structure is observed, mostly of vibronic origin. It is suggested that non totally symmetric modes of BEDT-TTF molecule can couple with electrons. J. Phys. France 51 (1990) 869-881 1 er MAI 1990,
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