First principles study of Ca₂PtO₄ in K₂NiF₄ and ‘post-K₂NiF₄' type structures

Samir F. Matar (1) , Gérard Demazeau (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

Deriving the energy-volume equations of state EOS for Ca₂PtO₄ in Ca₂IrO₄-type and in K₂NiF₄-type (knf) structures, leads to energy destabilization at a larger volume for the latter and to propose the former as a post-K₂NiF₄–pknf–occurring at high pressures with a reduced dimensionality 2D-knf → 1D-pknf and a rearrangement of the PtO₆ octahedra from corner sharing in knf to edge sharing in pknf. Bader charge analysis indicates an increased covalence of Pt–O bond with such a transformation. The lowered dimensionality is also illustrated from the density of states.

Domaines: Matériaux

Samir F. Matar, Gérard Demazeau. First principles study of Ca₂PtO₄ in K₂NiF₄ and ‘post-K₂NiF₄' type structures. Chemical Physics Letters, 2011, 503 (1-3), pp.49-52. ⟨10.1016/j.cplett.2010.12.054⟩. ⟨hal-00565256⟩