MAGNETIC-PROPERTIES OF DCNQI-CU SYSTEMS

Recent advances in the study of magnetic properties of a series of mol ecular conductors, Cu salts of DCNQIs, are presented. First, the antif erromagnetic order of Cu spins in the insulating phases below about 10 K is found to be accompanied by weak ferromagnetism with the spontane ous moment perpendicular to the tetragonal c-axis. Second, our suscept ibility study of the metal-insulator-metal (M-I-M) reentrant system, ( DMe-DCNQI-alpha,alpha'-d(2))(2)Cu, has lead to the absence of many-bod y enhancement of the susceptibility in the low temperature metallic ph ase. Finally, (DI-DCNQI)(2)Cu is found to exhibit considerably enhance d and temperature dependent susceptibility, suggesting the effect of s pin fluctuation in the metallic state.