A three-atomic model of crystals with supercritical behavior (Q2475219)

In the paper the modified Frenkel model is considered in which the potential energy is described by a fourth-degree polynomial in the displacement without potential barred. Note that this model is the three-atomic model with dissimilar end atoms. Due to dynamics theory, the calculated behavior of the middle atom that depends on the temperature, while the length is fixed, shows the phenomenon of supercritical transition connected, according to V. K. Semenchenko, with a passage of the stability determinant through a minimum without stability loss. If the forces applied to the end atoms are set rather then the model length, then an analysis shows a linear temperature dependence of the coefficients of elasticity.