One-dimensional electronic properties of the bechgaard salts

We discuss the relationship between the two possible descriptions of the one-dimensional electronic properties of the Bechgaard salts, namely: i) microscopic models, like the extended Hubbard model, directly related to quantum chemistry, and ii) effective low-energy models, like g-ology, used to interpret low-temperature experiments. We show that it is now possible to calculate several low-energy properties of one-dimensional microscopic models, like the critical exponents, the charge gap and the Pauli susceptibility, and that this leads to a new interpretation of low-temperature experimental data and resolves some of the contradictions in the field.