GROUND-STATE PHASE-DIAGRAM OF THE FALICOV-KIMBALL MODEL

The two-state spinless Falicov-Kimball model on a one-dimensional latt ice is studied by means of well-controlled numerical procedures. Restr icted phase diagrams in the grand-canonical ensemble and at zero tempe rature are constructed. The evolution of these phase diagrams, as the interaction parameter U is varied, along with the band structures corr esponding to configurations of localized particles (ions) and densitie s of mobile particles (electrons), is monitored. The changes observed enable us to draw conclusions for the complete phase diagram and to ma ke a qualitative plot of such a diagram.