QUASI-ONE-DIMENSIONAL ORGANIC METALS - THEORY AND EXPERIMENT

Given the success of the weak coupling nesting model in explaining the rmodynamical properties of the Bechgaard salts at low temperatures and in magnetic fields, we first concentrate on its implications to kinet ics in the metallic phase. The model results in nonuniversal temperatu re dependencies of resistivity and magnetoresistance due to proximity of the metallic and the spin density wave phases, which are in a quali tative agreement with the available experimental data. We then analyze whether the phenomenological nesting model can be justified in framew orks of a more general model of electron-electron interactions in the one-dimensional system improved by three-dimensional effects of the in terchain hopping. Properties of the Bechgaard salts look consistent wi th the Hubbard model with a weak repulsion. Considerable high temperat ure variation of the magnetic susceptibility is ascribed to localizati on of electrons by quasi-elastic scattering on thermal phonons. The fa ct that these materials correspond to the half-filled (hole) band was crucial for the analyses. Except for a new energy scale, introduced by the temperature of a spin density wave transition, no other electroni c correlation effects stem from the analysis.