Transport study of an organic conductor, θ-(BEDT-TTF)2I3

Pressurization of θ-(BEDT-TTF)2I3 has been shown to expand the cross-sectional area of small three-dimensional Fermi surface viewed along the bm-axis. At room temperature, θ-(BEDT-TTF)2I3 has been found to undergo a transition at about 5 kbar to a new phase (θh-phase), whose electric behavior is similar to that of the α-phase. The temperature dependence of the Hall coefficient of θ-(BEDT-TTF)2I3 has been interpreted by taking account of the thermal effect on large two-dimensional Fermi surface.