  The characteristics of the chiral phase transition are analyzed within the
framework of chiral quark models with nonlocal interactions in the mean field
approximation. In the chiral limit, we develop a semi-analytic framework which
allows us to explicitly determine the phase transition curve, the position of
the critical points, some relevant critical exponents, etc. For the case of
finite current quark masses, we show the behavior of various thermodynamical
and chiral response functions across the phase transition.
