Effect of intersite repulsions on magnetic susceptibility of one-dimensional electron systems at quarter filling

The temperature dependence of magnetic susceptibility, chi(T), is investigated for one-dimensional interacting electron systems at quarter filling within the Kadanoff-Wilson renorrualization-group method. The forward scattering on the same branch (the g(4)-process) is examined together with the backward (g(1)) and forward (g(2)) scattering amplitudes on opposite branches. In connection with lattice models, we show that chi(T) is strongly enhanced by the nearest-neighbor interaction, an enhancement which surpasses that of the next-nearest-neighbor interaction. A connection between our predictions for chi(T) and experimental results for chi(T) in quasi-one-dimensional organic conductors is presented.