The entropies and probable symmetries of the gaseous thorium and uranium tetrahalides
- SRI International, Menlo Park, California 94025 (US)
The sublimation entropies of the thorium and uranium tetrahalides (except UI{sub 4} ) have been evaluated from torsion--effusion vapor pressure measurements and the results have been analyzed for compatibility with the spectroscopic and molecular constants of the gaseous molecules. New effusion pressure measurements are reported here for UCl{sub 4}, UBr{sub 4}, and ThI{sub 4}. For UF{sub 4}, UCl{sub 4}, and ThF{sub 4}, where thermal data are available for the solid phases, the experimental entropies of gaseous UF{sub 4} and UCl{sub 4} are incompatible with regular tetrahedral symmetries, while that of ThF{sub 4} is in close accord with a {ital T}{sub {ital d}} structure. A comparison of the entropies of sublimation shows that ThCl{sub 4} most likely has {ital T}{sub {ital d}} symmetry, while UBr{sub 4}, ThBr{sub 4}, and ThI{sub 4} probably do not; less-reliable total entropy data for the species are in full accord with these conclusions. The results are discussed in terms of structural information in the literature.
- OSTI ID:
- 5589696
- Journal Information:
- Journal of Chemical Physics; (USA), Journal Name: Journal of Chemical Physics; (USA) Vol. 94:12; ISSN JCPSA; ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
Similar Records
High-temperature equilibrium studies of the gaseous thorium chlorides
Bond Dissociation Energies and Electronic Calculations on the Actinide Halides ThX and UX (X = Cl, Br, I)
Related Subjects
400201* -- Chemical & Physicochemical Properties
ACTINIDE COMPOUNDS
BROMIDES
BROMINE COMPOUNDS
CHLORIDES
CHLORINE COMPOUNDS
ENTROPY
EVAPORATION
FLUIDS
FLUORIDES
FLUORINE COMPOUNDS
GASES
HALIDES
HALOGEN COMPOUNDS
IODIDES
IODINE COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SUBLIMATION
SYMMETRY
THERMODYNAMIC PROPERTIES
THORIUM BROMIDES
THORIUM CHLORIDES
THORIUM COMPOUNDS
THORIUM FLUORIDES
THORIUM IODIDES
URANIUM BROMIDES
URANIUM CHLORIDES
URANIUM COMPOUNDS
URANIUM FLUORIDES
URANIUM TETRAFLUORIDE
VAPOR PRESSURE