By the reaction of a new donor molecule, ethylenedithiotetrathiafulvalenoquinone-1,3-dithiolemethide (1) with FeBr
3, GaBr
3 or FeCl
3 in CH
3CN/CS
2 charge transfer (CT) salts of 1 with ...counteranions of FeBr
4
−, GaBr
4
− or FeCl
4
− (1
2·FeBr
4, 1
2·GaBr
4 and 1
2·FeCl
4) as plate crystals were obtained. Their crystal structures are apparently similar to each other, in which 1 molecules are dimerized in the parallel direction of their molecular long axes, and the dimers are stacked with changing the direction of the molecular long axes alternately to form a one- dimensional column. The counteranions intervene between the 1-stacked columns and are aligned in a zigzag manner. The room-temperature electrical conductivities of 1
2·FeBr
4 and 1
2·GaBr
4 are fairly high (10–15 S cm
−1), but a small value (0.8 S cm
−1) is obtained for 1
2·FeCl
4. For all CT salts, temperature dependences of electrical conductivity are semiconducting in spite of very small activation energies (30–90 meV). Based on the comparison between their electrical conducting and magnetic properties, it is suggested that the
d spins of FeBr
4
− or FeCl
4
− ions exert almost no influence on the π conducting electrons in the 1-stacked column.
It has been known that the new donor ND1 whose deep-level transient spectroscopy (DLTS) peak appears at about 33 K can be generated in two-step heat treated (723 and 923 K) carbon-rich n-type CZ ...silicon. In this study, the annihilation process of the new donor ND1 is studied by a combination of electrical measurement, DLTS and Fourier transform infrared spectroscopy (FTIR). The results show that the ND1 is annihilated by annealing at temperatures above 1073 K. The size of the ND1 cluster is not the same, but distributes in a certain range. The ND1 loses its electrical activity by both decomposition and growth of the ND1 cluster during the annealing. Annealing at a temperature between 1073 and 1273 K would delay the ND1 annihilation by decomposition and enhance that by growth in the subsequent annealing at a higher temperature.
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