Materials Data on CaP2H8(CO3)2 by Materials Project
CaP2H8(CO3)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two CaP2H8(CO3)2 sheets oriented in the (1, 0, 0) direction. Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with six equivalent PCO3 tetrahedra and edges with two equivalent CaO6 octahedra. There are four shorter (2.41 Å) and two longer (2.44 Å) Ca–O bond lengths. C4- is bonded in a distorted tetrahedral geometry to one P5+ and three H1+ atoms. The C–P bond length is 1.80 Å. All C–H bond lengths are 1.10 Å. P5+ is bonded to one C4- and three O2- atoms to form PCO3 tetrahedra that share corners with three equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–66°. There is two shorter (1.53 Å) and one longer (1.59 Å) P–O bond length. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.63 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C4- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C4- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C4- atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one P5+, and one H1+ atom.