Spin dynamics in the charge ordered state of (DI-DCNQI)2Ag with a quasi-one-dimensional quarter-filled band

NMR measurements have been performed to investigate the spin dynamics in the insulating state of the quasi-one-dimensional conductor, (DI-DCNQI)2Ag. A charge ordering with 4kF modulation has been evidenced below 220K by the line separation of the 13CNMR spectra, which shows a clear charge disproportionation instead of the lattice dimerization encountered in most cases. The T1 −1 and t2−1 have been measured at the electron “rich” and “poor” sites separately. The results reflect different profiles of the spin fluctuations at the two sites.