LAUSR

Sodium fluorouranates were studied to get the refined value of one of the fundamental constants with determination of differences between various uranium isotopes contained in these compounds. Such compounds as sodium heptafluorouranate can be classified as molecular substances with covalent bonds. The approach to the assessment of decomposition temperature of sodium fluoride compounds with various uranium isotopes based on the Mendeleev and Karapetyants methods, as well as on the quantum Landau representations is proposed. The Landau equation for the boiling point of isotopic compounds was corrected. The estimated decomposition (boiling) temperatures of sodium heptafluorouranates containing uranium isotopes 235U, 234U, and 232U were 453.8, 453.0, and 451.4 K respectively. The sublimation temperature of 271SgF6 was estimated.