Kinetic model of polymorphic transitions in molecular crystals

A polychromous model in the form of an integral equation of first kind is suggested for autocatalytic polymorphic transitions of arbitrary order in molecular crystals. The model relates the observed heat absorption to the distribution of the volume of the crystalline substance over the concentrations of the initial and final modifications. The activation energy of the polymorphic transition has been calculated. The inverse problem of reconstructing the distribution function from experimental data has been solved. The model is in good quantitative and qualitative agreement with calorimetric data.