THE THERMODYNAMICS OF SUBLIMATION AND VAPORIZATION OF SOME VOLATILE BETA-DIKETONATES COMPLEXES WITH THE ELEMENTS OF HTSC PHASES

The processes of sublimation and vaporization of six beta-diketonate c omplex compounds of rare-earth metals, Ba and Cu with pivaloyltrifluor oacetone (Hpta) and hexafluoro-acetylacetone (Hhfa) have been studied at different temperatures by the tensimetric flow method. The vapour p ressure of the tetrakis chelate Na[Y(pta)4] was also determined by the static method with a silica-membrane zero gauge. These results are in agreement with the data obtained by the flow method. The dependencies of vapour pressure on temperature, and the thermodynamic characterist ics of vaporization and sublimation of the listed compounds are report ed.