Materials Data on Li4Fe(PO4)2 by Materials Project
Li4Fe(PO4)2 is Clathrate-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. 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 PO4 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.00–2.08 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four PO4 tetrahedra, corners with six LiO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.99–2.07 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra, corners with two equivalent FeO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.98–2.09 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with four LiO4 tetrahedra, and corners with four PO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.94–2.00 Å. Fe2+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four LiO4 tetrahedra and corners with four PO4 tetrahedra. There are two shorter (2.02 Å) and two longer (2.03 Å) Fe–O bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra and corners with eight LiO4 tetrahedra. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra and corners with eight LiO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and one P5+ atom to form a mixture of distorted corner and edge-sharing OLi3P trigonal pyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded to three Li1+ and one P5+ atom to form a mixture of distorted corner and edge-sharing OLi3P tetrahedra. In the fourth O2- site, O2- is bonded to three Li1+ and one P5+ atom to form a mixture of corner and edge-sharing OLi3P tetrahedra. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded to three Li1+ and one P5+ atom to form corner-sharing OLi3P tetrahedra. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Fe2+, and one P5+ atom.