Thermoelastic Properties of MgSiO3 and CaSiO3 Perovskites under Lower-Mantle Conditions.
نویسندگان
چکیده
منابع مشابه
Modeling the melting of multicomponent systems: the case of MgSiO3 perovskite under lower mantle conditions
Knowledge of the melting properties of materials, especially at extreme pressure conditions, represents a long-standing scientific challenge. For instance, there is currently considerable uncertainty over the melting temperatures of the high-pressure mantle mineral, bridgmanite (MgSiO3-perovskite), with current estimates of the melting T at the base of the mantle ranging from 4800 K to 8000 K. ...
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First-principles molecular dynamics calculations were performed in order to investigate the structure and properties of what is thought to be the third most abundant phase in the Earth’s lower mantle, CaSiO3 perovskite. The commonly assumed cubic structure was found to be stable at high temperatures T 1000–2000 K and unstable at low temperatures at all pressures. For this structure we investiga...
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ژورنال
عنوان ژورنال: THE REVIEW OF HIGH PRESSURE SCIENCE AND TECHNOLOGY
سال: 1998
ISSN: 0917-639X,1348-1940
DOI: 10.4131/jshpreview.7.113