Pozhivatenko V. The modeling of the hierarchical processes in the alkaline-earth metals chalcogenides under pressure

Dissertation devote to the working out new approach for calculation properties of the alkaline-earth metals chalcogenides (AEMC). In joint calculation method which union the electron density functional theory, the norm-conserving pseudopotential method and self-interaction correction put into practice the study of the equilibrium properties alkaline-earth metals and their chalcogenides (equilibrium atomic volumes, total energy, research of the stability of the crystal structures), properties of the electron subsystem (electron band structures and their peculiarities), the properties under pressure (the equations of state, structural phase transition fcc-bcc in alkaline-earth metals and B1 - B2 in alkaline-earth metals chalcogenides under pressures, pressure induced dielectric - metal transition, change of the electron subsystem properties under pressure). The method for the hierarchically error reduction in the LDA-calculation is proposed. Phase transition characteristics of AEMC were calculated for the six states of equations. It was shown that Birch state of equation with the used assumptions is precise enough for AEMC behavior description under moderate pressures.