The thermodynamic properties of rhenium on ITS-90

Rhenium exists in a close-packed hexagonal structure with lattice parameters at 293 K of a = 0.27610 nm c = 0.44583 nm and a density of 21.01 g cm−3 (Donohue [1] corrected for conversion factors recommended in the 1986 revision of the fundamental constants [2]). Wherever possible values have been corrected to the currently accepted atomic weight of 186.207 [3] and to the revision of the ITS-90 temperature scale [4,5]. The melting point determined by Sims, Craighead and Jaffee [6] corrects to 3458 ± 20 K on this scale. A superconducting transition temperature (Tc) of 1.700 K takes in to account the recommended values of both Roberls [7] and Hultgren et al [8]. The previous review of the thermodynamic properties was by the latter authors.