Hydration of selected divalent. beta. double prime -aluminas

Journal Article · · Chemistry of Materials; (USA)

OSTI ID:5562946

Rohrer, G S; Farrington, G C ^[1]; Thomas, J O ^[2]

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1. Univ. of Pennsylvania, Philadelphia (USA)
2. Univ. of Uppsala (Sweden)

The absorption and desorption of H{sub 2}O by Ca(II)-{beta}{double prime}-alumina, Ba(II)-{beta}{double prime}-alumina, and Ba(II)-{beta}{double prime}-ferrite were studied by thermogravimetry, differential scanning calorimetry, and evolved gas analysis, and the crystal structures of Ba{sub 0.83}Mg{sub 0.67}Al{sub 10.33}O{sub 17}{center dot}(H{sub 2}O){sub 0.64} and Ca{sub 0.83}Mg{sub 0.67}Al{sub 10.33}O{sub 17}{center dot}(H{sub 2}O){sub 1.0} were determined by the refinement of single-crystal X-ray diffraction data. The crystals are in the rhombohedral space group, R{bar 3}m, and have three formula units per hexagonal unit cell. The hexagonal cell dimensions for the hydrated Ba(II) isomorph area a = 5.617 (1) {angstrom}, c = 34.115 (8) {angstrom}, and V = 932.2 (4) {angstrom}{sup 3}, and for the hydrated Ca(II) isomorph are a = 5.628 (1) {angstrom}, c = 33.837 (11) {angstrom}, and V = 928.2 (4) {angstrom}{sup 3}. A comparison with previously reported data for other isomorphs indicates that in {beta}{double prime}-alumina-type compounds absorbed water appears to interact more strongly with the structural framework than with the mobile cations.

• OSTI ID: 5562946
• Journal Information: Chemistry of Materials; (USA), Journal Name: Chemistry of Materials; (USA) Vol. 3:2; ISSN CMATE; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
BARIUM COMPOUNDS
CALCIUM COMPOUNDS
CALORIMETRY
CHALCOGENIDES
CHEMICAL ANALYSIS
COHERENT SCATTERING
CRYSTAL STRUCTURE
DIFFRACTION
FERRIMAGNETIC MATERIALS
FERRITES
GRAVIMETRIC ANALYSIS
HYDRATION
IRON COMPOUNDS
MAGNETIC MATERIALS
MATERIALS
OXIDES
OXYGEN COMPOUNDS
QUANTITATIVE CHEMICAL ANALYSIS
SCATTERING
SOLVATION
SPACE GROUPS
THERMAL ANALYSIS
THERMAL GRAVIMETRIC ANALYSIS
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION