ISSN:
1432-2021
Keywords:
Key words Aluminum oxide hydroxide
;
Hydrous mineral
;
High-pressure
;
Transition zone
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
Abstract A new phase of AlOOH (tentatively called δ-AlOOH) was synthesized at 21 GPa and 1000 °C and its crystal structure was identified by a powder X-ray diffraction method. Rietveld refinement revealed that this aluminum oxide hydroxide has an orthorhombic unit cell, a = 4.7134(1) Å, b = 4.2241(1) Å, c = 2.83252(8) Å, V = 56.395 (5) Å3, and Z = 2 in the space group of P21 nm. A calculated density is 3.533 g cm−3, which is about 4.48 and 15.04% denser than that of diaspore and boehmite, respectively. The δ-[Al0.86Mg0.07Si0.07]OOH is also stable at 21 GPa and 1000 °C, coexisting with majorite and phase egg, and its cell parameters are a = 4.710(1) Å, b = 4.215(1) Å, c = 2.839(1) Å, and V = 56.37(1) Å3.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002690000120
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