X-Ray Investigations of the Low-Temperature Phases
نویسندگان
چکیده
The structure of single crystals of the organic metals aand /?-(BEDT-TTF)2I3* was determined at 100 K, well below the phase transitions indicated by resistivity and thermopower measurements as well as by differential thermal analysis. In the a-phase no unusual change of the room temperature unit cell but a slight variation in the triiodide network and especially a more pronounced dimerization in one of the two donor stacks have been found. The /?-phase develops a superstructure with a unit cell volume three times as large as that at room temperature and with pronounced distortions of the I 3-ions.
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