The Vapour Pressures of Some Heavy Transition Metal Hexafluorides
Abstract
The vapour pressures of the hexafluorides of tungsten, molybdenum, rhenium, osmium and iridium have been measured by a static method using a diaphragm gauge of high sensitivity. Hitherto unknown solid-solid transitions are reported for rhenium, osmium and iridium hexafluorides together with those known for tungsten and molybdenum hexafluorides. These are, respectively: -1.90 degree, -0.4 degree, 40.4 degree, -8.2 degree, and -8.7 degree. From the vapour pressure data more accurate physical constants, latent heats of vaporisation, and sublimation, heats of fusion and transition, and entropies of fusion, transition and vaporisation have been calculated. Nuclear magneticresonance studies with both solid and liquid hexafluorides suggest that there is molecular rotation in the solid state above the transition point.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1960
- Accession Number
- AD0243296
Entities
People
- George B Hargreaves
- George H. Cady
Organizations
- Washington University in St. Louis