ESTIMATION OF CRITICAL-TEMPERATURES OF RB AND CS BY AN INTERNAL-PRESSURE APPROACH AND THEIR COMPARISON WITH THOSE OF OTHER ALKALI-METALS

The internal pressure approach (IPA) has been used to compute Tc of Rb and Cs to be 1935±87 and 1915±94 K, respectively, based on recent data on their thermophysical properties from the literature. These values are compared with the literature data based on other methods and with the Tc values of Li, Na and K which have also been computed by IPA using the latest assessed thermophysical data. A systematic trend in the Tc values of alkali metals with atomic radius has been identified whose correlation to the interatomic attraction in the alkali metals has been discussed.