Ii nmr study in 2-D mott-hubbard system, (BEDT-TTF) (TCNQ)

Summary form only given. (BEDT-TTF) (TCNQ) is composed of 2D-conducting sheets of BEDT-TTF and 1-D TCNQ columns. The band calculation predicts a metallic state in (BEDT-TTF) (TCNQ), whereas it shows the metal-insulator transition at T/sub MI/, 330K at ambient pressure. In order to investigate an electronic state in (BEDT-TTF) (TCNQ), we have performed the H-NMR measurement. We have found that there exist two magnetically different proton sites. An anomalous broadening of the main H-NMR linewidth and a peak of l/T/sub 1/ were observed at T/sub N/=3K, where a antiferromagnetic order of TCNQ columns was suggested from the anisotropic susceptibility measurement. Experimental results on M-I transition will be also presented.