By calculating thermodynamics properties of a Hubbard model on the anisotropic triangular lattice close to the isotropic point, we clearly observe a metal-insulator transition in the charge susceptibility and estimate critical interaction strength for such transition at different extends of frustrations. Determined phase diagram gives support to other numerical methods like variational Monte Carlo and path integral renormalization group and reveals that other methods like slave rotors, resonating valence bond theory, dynamical mean field theory and Brinkman-Rice approach gives substantially different value for a critical interaction strength. In the metallic side we observed Fermi liquid like behavior in charge susceptibility, entropy and specific heat and show that this phase crosses over to incoherent (bad metallic) phase at relatively low coherence temperature. Our results for the coherence temperature and quasi-particle mass renormalization in Fermi liquid phase agree well with experiments on organic charge transfer salts, which therefore give support to the description of these rather complicated molecular crystals with relatively simple microscopic model. Results on spin susceptibility, entropy and estimate of double occupancy show that in the bad metallic phase fluctuating local magnetic moment is already large and in this way give support to the picture of this phase proposed by dynamical mean field theory. In the insulating phase we demonstrate how frustration increases density of low lying spin excitations, which is, e.g., reflected in the maximum of the specific heat being at temperatures much below the energy of an exchange interaction.
COBISS.SI-ID: 26760743