Kentuckia: A 4-,6-,8-Connected Tetragonal Structural Pattern in Space Group P4/Nmm

Abstract

This paper describes the crystal structure of a novel, hypothetical 4-,6-,8- connected tetragonal structural pattern with the ternary stoichiometry ABC. The novel pattern lies in space group P4/nmm, number 129. It possesses the Wells point symbol (4)(46)(4) and has the Wellsean Schläfli index (4.4615, 6). The structure-type could be representative of a ternary bimetallic oxide in which the 2 oxygens within the unit cell adopt octahedral coordination with respect to two different metal atoms. The square planar vertices in Kentuckia’s structure could likely represent Ni group atoms (such as formally Pt cations). The octahedral vertices could represent O atoms, as formally O anions, in which both of the lone pairs on the O atom are used in dative bonds with the other metal centers (counterions). And the 8-connected cube centered vertices could represent alkaline earth metals with the 2+ oxidation state, such as Ca Such a bimetallic oxide would contain metal to non-metal bonds between the 4 octahedral sites and the 2 cube-centered sites, and the 4 octahedral sites and the 2 square planar sites. A probable phase might be CaPtO. For a configuration of this lattice in which / is equal to 1/2, the structure has no angle strain.

Keywords: Physical Chemistry > Solid State Chemistry and Materials, physchem/0201014