New supramolecular copper complexes with pyrazinotetrathiafulvalene (pyra-TTF) as the ligand, [(CUCl2)-Cl-II(pyraTTF)] (1) and (pyra-TTF)(2)[(CU3Cl4)-Cl-I(pyra-TTF)] (2), have been synthesized by-the diffusion method. Complex 1 is a black block crystal with a three-dimensional (3-D) supramolecular network; the linear chain [-(CUCl2)-Cl-II-(pyra-TTF)-](n) extends along the b axis, where the coordinated pyra-TTF donors are stacked in a head-to-tail and ring-over-bond configuration to construct two-dimensional (2-D) sheets, and between the sheets, there are C center dot center dot center dot Cl- or H center dot center dot center dot Cl- contacts. Even though the electron spin resonance (ESR) measurement reveals the nearly Cu-II state, complex 1 is a semiconductor with sigma(RT) = 1.0 X 10(-4) S cm(-1) and E-a = 0.33 eV. The high-frequency conductivity measurement also confirmed the intrinsic slight carrier doping from Cu-II to the pyra-TTF donor. This slight doping enhances not only the real and imaginary dielectric constants but also the antiferromagnetic interaction between Cu-II spins following the 2-D Heisenberg model with 2J = -20 K. In contrast, complex 2 is a very thin black needle. This needle crystal has two crystailographically independent pyra-TTF molecules, which are coordinated and noncoordinated donors. The coordinated donors composed a supramolecular chain [(Cu3Cl4)-Cl-I(pyra-TTF)(0)](n), whereas the noncoordinated donors formed conducting alpha ''-type pyra-TTF+0.5 sheets. This complex is semiconducting with sigma(RT) = 0.1 S cm(-1) and E-a = 0.15 eV. Both complexes 1 and 2 demonstrate that the pyra-TTF molecule works not only as an oxidized donor by Cu-II to construct conducting sheets but also as a ligand coordinated to a Cu cation to form supramolecuar chains.