Materials Data on K2PO4 by Materials Project
K2PO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of K–O bond distances ranging from 2.77–3.20 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.70–2.98 Å. P is bonded in a tetrahedral geometry to four O atoms. There is three shorter (1.53 Å) and one longer (1.70 Å) P–O bond length. There are four inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to five K and one P atom. In the second O site, O is bonded in a distorted single-bond geometry to five K and one P atom. In the third O site, O is bonded in a distorted single-bond geometry to three K and one P atom. In the fourth O site, O is bonded in a distorted single-bond geometry to four K and one P atom.