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The unusual thermodynamic properties of cerium result from features in the narrow 4f-zone whose electrons are subdivided into localized and delocalized subsystems. In this paper the model of pseudo-binary solid solutions allowing for two different electronic states is applied to construct the thermodynamically complete two-phase equation of state for cerium. The parameters of the model were fitted to describe the thermodynamic data obtained in the static experiments with high-purity cerium. This equation of state was used to analyze wave structures realized under dynamic compression with regard to the equilibrium (γ,α) phase transition.Cerium possesses a great variety of unusual properties among which are the presence of a critical point on the line of the isomorphic (γ-α)-transition and also the anomalous behavior of elastic and thermal properties in its neighborhood. Furthermore, the phase diagram of cerium, which contains a great number of phases, is characterized by considerable complexity and inconsistency.Investigations into the phase diagram and properties of cerium in the high-pressure region were pursued under static [1-12] and dynamic [13][14][15] compression conditions. In this paper the dynamic compression of Ce is considered with the use of a thermodynamically complete two-phase equation of state (EOS) for the γ-and α-phases. As the basis for the formulation of the equation of state, the model of pseudobinary solid solutions, developed by Aptekar and Ponyatovsky [16], is applied for the description of anomalous behavior of Ce in the neighborhood of the (γ-α)-transformation. In the model, cerium is presented as a solid substitution solution composed of Ce atoms in various electronic states. According to present views, a difference in the electronic states of the α-and γ-phases is in various screening levels of spins of localized 4f electrons (Kondo volume-collapse model), or in localization (γ-phase) and delocalization (α-phase) of 4f electrons (Mott transition). But for the semi-empirical model, the refinement of electronic states is of little significance; their energy closeness is a decisive factor.The specific (per mole) thermodynamic Gibbs potential for the mixture of two kinds of cerium atoms being in sites of the fcc lattice is written in the form [16], G

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