Ab initio investigation of perovskite and post-perovskite CaPtO3
نویسندگان
چکیده
For the recently synthesized post-perovskite (PPV) CaPtO3 we investigate the electronic band structure properties in connection with hypothetical perovskite PV–CaPtO3 within density functional theory using pseudopotential and all electron methods. Both systems are found insulating in agreement with a tetravalent Pt(IV) low spin d6 state. The equilibrium values of the volume and energy point to a stabilization of the PPV versus PV oxide with a smaller volume in agreement with other homologue systems within Earth lower mantle such as PPV–MgSiO3. This is also addressed from the analysis of the chemical bonding focusing on the change of the Pt–O bonding upon going from PV and PPV systems whereby the covalent Pt–O bonds are differentiated and reinforced within PPV system with respect to PV.
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