Materials Data on KCaPO5 by Materials Project
KCaPO5 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.87–3.25 Å. Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.54 Å. P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. There are four inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to one K, two equivalent Ca, and one P atom. In the second O site, O is bonded in a distorted single-bond geometry to four equivalent K and one P atom. In the third O site, O is bonded in a distorted single-bond geometry to two equivalent K, two equivalent Ca, and one P atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to two equivalent Ca atoms.