  We give a survey on the predictions of Coulombic phase transitions in dense
plasmas (PPT) and derive several new results on the properties of these
transitions. In particular we discuss several types of the critical point and
the spinodal curves of quantum Coulombic systems. We construct a simple
theoretical model which shows (in dependence on the parameter values) either
one alkali-type transition (Coulombic and van der Waals forces determine the
critical point) or one Coulombic transition and another van der Waals
transition. We investigate the conditions to find separate Van der Waals and
Coulomb transitions in one system (typical for hydrogen and noble gas-type
plasmas). The separated Coulombic transitions which are strongly influenced by
quantum effects are the hypothetical PPT, they are in full analogy to the known
Coulombic transitions in classical ionic systems. Finally we give a discussion
of several numerical and experimental results referring to the PPT in high
pressure plasmas.
