Measurement of Thermopower Force of Small Fragile Crystals and Multistep Metal-Insulator Transition of 2-Band Quasi-One-Dimensional Organic Conductors

摘要

The technique to measure thermopower of a small fragile crystal is presented with the method of data correction. The typical length of the sample is from 0.5 to 1.5mm. One can determine the absolute thermopower of the sample between 4.2and 300 K by this technique but it is easily developed for the application at higher temperatures. Phase transitions observed for (DMET)_2ClO_4 (DMET=dimethyl (ethylenedithio)diselenadithiafulvalene) and its analogues, which have two kinds of quasi-one-dimensional conducting donor columns, are studied by utilizing the present technique to measure the thermopower.