Materials Data on Ca5As3CO12 by Materials Project
Ca5(AsO4)3C crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional and consists of two methane molecules and one Ca5(AsO4)3 framework. In the Ca5(AsO4)3 framework, there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.43–2.94 Å. In the second Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.52 Å. As+3.33+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of As–O bond distances ranging from 1.71–1.74 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+ and one As+3.33+ atom. In the second O2- site, O2- is bonded to three Ca2+ and one As+3.33+ atom to form distorted edge-sharing OCa3As tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As+3.33+ atom.