ABSTRACT
This chapter describes the design of molecular organic superconductors (SCs) and the structural and physical aspects of one-dimensional, 2D, and 3D SCs as the representatives of the 11 families. The electronic properties of ET indicate that while it is a slightly weaker donor than tet-ramethyltetraselenafulvalene (TMTSF) it is better than TMTSF in yielding conductive charge transfer complexes. The ET molecules in a complex form stack with molecules displaced in terms of overlap so as to minimize the steric hindrance caused by the ethylene group(s), leaving cavities along the direction of the molecular long axis, where counteranions and sometimes solvent molecules may reside. The nonperiodicity can be chemically produced by the use of low-symmetric component molecules or physically produced by the irradiation of a complex to form defects or disorder in the crystals. The conduction electrons are strongly correlated in the metallic state to give rise to curious phenomena.
