Stable compounds in the CaO-Al2O3 system at high pressures
نویسندگان
چکیده
Using the evolutionary crystal structure prediction algorithm USPEX, we showed that at pressures of Earth’s lower mantle (24-136 GPa) CaAl2O4 is only stable calcium aluminate. At above 7.0 GPa it has CaFe2O4-type with space group Pnma. This phase one prime candidate aluminous phases in Earth. We show low 5CaO • 3Al2O3 (C5A3) Cmc21, CaAl4O7 (with C2/c) and (space P21/m) are up to 2.1, 1.8 GPa, respectively. The previously unknown orthorhombic "CA-III" also found our calculations. metastable 0 K a layered P21212.
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ژورنال
عنوان ژورنال: Physics and Chemistry of Minerals
سال: 2022
ISSN: ['1432-2021', '0342-1791']
DOI: https://doi.org/10.1007/s00269-022-01221-6