DOE OSTI2020
KH2PO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 1-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.79–3.00 Å. In the second K1+ site, K1+ is bonded in a 1-coordinate geometry to three H1+ and seven O2- atoms. There are a spread of K–H bond distances ranging from 2.83–2.96 Å. There are a spread of K–O bond distances ranging from 2.82–3.11 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the second P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to one K1+ and two O2- atoms. There is one shorter (1.06 Å) and one longer (1.43 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a linear geometry to one K1+ and two O2- atoms. There is one shorter (1.08 Å) and one longer (1.39 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a distorted linear geometry to one K1+ and two O2- atoms. There is one shorter (1.04 Å) and one longer (1.49 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.03 Å) and one longer (1.56 Å) H–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one P5+, and one H1+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one P5+, and one H1+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to two equivalent K1+, one P5+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one P5+, and one H1+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to three K1+, one P5+, and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one P5+, and one H1+ atom.