Charge transfer complexes of OCNAQ with pyrene, PT (phenothiazine), TMTTF (tetramethyltetrathiafulvalene), TTF (5,6 : 11,12-bis(epidithio)naphthacene), and TTF (tetrathiafulvalene) have been prepared. The pyrene and PT complexes are electrically insulating and the ground state is neutral. In most of the other complexes OCNAQ is fully charged. One of the TTT complexes, (TTT)2OCNAQ(DMF), where DMF is N,N-dimethylformamide, has been found to show metallic conductivity. A structural study has revealed that short S···N contacts exist between TTT and OCNAQ, in addition to one-dimensional TTT stacks. This transverse interaction has been demonstrated by the small anisotropy of the conductivity. The 2 : 1 TTF complex is also metallic down to 43 K, at which point a metal-to-insulator transition occurs. A structure analysis and thermoelectric power data suggest that the charge conduction in this crystal takes place not only through the TTF stacks but also through a two-dimensional network of the OCNAQ molecules.
制备了 OCNAQ 与
芘、
PT(
吩噻嗪)、
TMTTF(四甲基四
噻吩)、
TTF(5,6 : 11,12-双(二
硫代)
萘)和
TTF(四
噻吩)的电荷转移络合物。
芘和
PT 复合物具有电绝缘性,基态为中性。在大多数其他络合物中,OCNAQ 是完全带电的。其中一种
TTT 复合物 (
TTT)2OCNAQ(
DMF)(其中
DMF 是
N,N-二甲基甲酰胺)具有
金属导电性。结构研究显示,除了一维
TTT 叠层之外,
TTT 和 OCNAQ 之间还存在短的 S-N 接触。电导率的微小各向异性证明了这种横向相互作用。2 : 1
TTF 复合物在低至 43 K 时也具有
金属性,此时会发生
金属到绝缘体的转变。结构分析和热电功率数据表明,这种晶体中的电荷传导不仅通过
TTF 叠层进行,而且还通过 OCNAQ 分子的二维网络进行。