H-1-NMR STUDIES OF (DME-DCNQI-D(7))(2)CU1-XLIX

Systematic measurements of H-1-NMR relaxation rate, T-1(-1), in the or ganic conductor, (DMe-DCNQI-d(7))(2)Cu1-xLix(x=0.04, 0.5 similar to 0. 6, 1), have been carried out, to clarify the effect of Li doping on th e electronic properties of p pi-band. Within const. In a highly the st able metallic region (up to about x=0.5), T-1(-1) exhibits a Korringa- like behavior, (T1T)(-1)=const. In a highly doped sample, a nonmetalli c phase appears at low temperatures. The absolute value of T-1(-1) in the metallic region increases remarkably with the Li concentration and becomes the largest in the pure Li-salt, (DMe-DCNQI-d(7))(2)Li. This behavior is analyzed as a low-dimensional spin-diffusion effect.