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The standard thermodynamic constants are very important for all branches of science. The correct description of the heat capacities in a wide temperature range is especially difficult to find a solution. The nontrivial concept permitted us the possibility to find a fairly simple solution to this issue. This solution helped to describe the specific heat in a wide temperature range of a large class of isostructural sphalerite phases as a single system unambiguously. A fragmental description of some phase is like a vision of one part of a large mosaic picture. A single description of such a phase does not allow one to see the integrity of the entire ensemble. The 4th group of pure elements in addition to diamond, silicon, germanium, alpha tin, and diamond-like lead was taken as the base. Flerovium (114Fl) closes this group. There should be no other elements in this group according to the fine structure constant or the Sommerfeld constant α. As a consequence, the limiting value of the heat capacities of phases with a sphalerite structure falls on the 114th element (114Fl) and has a value of Cp = 30.5 J · mol-at-1 · K-1. This value arises when plotting the isotherms Ln (Cp / R) versus Ln (N), where N is an atomic number of an element of the IV group or the sum of atomic numbers of AIIIBV or AIIBVI compounds per mole-atom. This method can be applied to the other isostructural.