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We analyze the transformation from insulator to metal induced by thermalfluctuations within the Falicov-Kimball model. Using the Dynamic Mean FieldTheory (DMFT) formalism on the Bethe lattice we find rigorously the temperaturedependent Density of States ($DOS$) at half filling in the limit of highdimensions. At zero temperature (T=0) the system is ordered to form thecheckerboard pattern and the $DOS$ has the gap $\Delta$ at the Fermi level$\varepsilon_F=0$, which is proportional to the interaction constant $U$. Withan increase of $T$ the $DOS$ evolves in various ways that depend on $U$. For$U>U_{cr}$ the gap persists for any $T$ (then $\Delta >0$), so the system isalways an insulator. However, if $U < U_{cr}$, two additional subbands developinside the gap. They become wider with increasing $T$ and at a certain$U$-dependent temperature $T_{MI}$ they join with each other at$\varepsilon_F$. Since above $T_{MI}$ the $DOS$ is positive at $\varepsilon_F$,we interpret $T_{MI}$ as the transformation temperature from insulator tometal. It appears, that $T_{MI}$ approaches the order-disorder phase transitiontemperature $T_{O-DO}$ when $U$ is close to 0 or $ U_{cr}$, but $T_{MI}$ issubstantially lower than $T_{O-DO}$ for intermediate values of $U$. Havingcalculated the temperature dependent $DOS$ we study thermodynamic properties ofthe system starting from its free energy $F$. Then we find how the orderparameter $d$ and the gap $\Delta $ change with $T$ and we construct the phasediagram in the variables $T$ and $U$, where we display regions of stability offour different phases: ordered insulator, ordered metal, disordered insulatorand disordered metal. Finally, we use a low temperature expansion todemonstrate the existence of a nonzero DOS at a characteristic value of U on ageneral bipartite lattice.

Gapless metallic charge-density-wave phase driven by strong electron correlations