Materials Data on Li2PH3O4 by Materials Project
Li4P2H4O7H2O crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four water molecules and two Li4P2H4O7 sheets oriented in the (0, 0, 1) direction. In each Li4P2H4O7 sheet, there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four LiO4 tetrahedra, corners with four PHO3 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.93–2.07 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three PHO3 tetrahedra and corners with five LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.96–2.04 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three LiO4 tetrahedra, corners with four PHO3 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.95–1.99 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four LiO4 tetrahedra, corners with four PHO3 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.90–2.12 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to one H+0.33+ and three O2- atoms to form distorted PHO3 tetrahedra that share corners with eight LiO4 tetrahedra. The P–H bond length is 1.41 Å. There is one shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. In the second P5+ site, P5+ is bonded to one H+0.33+ and three O2- atoms to form distorted PHO3 tetrahedra that share corners with seven LiO4 tetrahedra. The P–H bond length is 1.42 Å. There are a spread of P–O bond distances ranging from 1.53–1.55 Å. There are four inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one P5+ atom. In the third H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one P5+ atom. In the fourth H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the second O2- site, O2- is bonded to three Li1+ and one P5+ atom to form corner-sharing OLi3P tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two H+0.33+ atoms. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the fifth O2- site, O2- is bonded to three Li1+ and one P5+ atom to form distorted corner-sharing OLi3P tetrahedra. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Li1+ and one P5+ atom.