μSR study of an antiferromagnetic insulator (BEDT-TTF)(TCNQ)

Zero-field μSR measurements for an antiferromagnetic Mott insulator (BEDT-TTF)(TCNQ) were performed for the first time in order to study the microscopic magnetic properties of this organics. Slight increase of the relaxation rate is observed below 20 K owing to the antiferromagnetic ordering of BEDT-TTF dimers, whereas clear muon precession signal is observed below 3 K owing to the antiferromagnetic ordering of TCNQ. Below 3 K, there exist at least two antiferromagnetic domains whose volume fractions changes with temperature.