Materials Data on Na5SiP3 by Materials Project
Na5SiP3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are five inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 3-coordinate geometry to five P+0.33- atoms. There are a spread of Na–P bond distances ranging from 2.86–3.46 Å. In the second Na1+ site, Na1+ is bonded in a 4-coordinate geometry to two equivalent Si4- and five P+0.33- atoms. There are one shorter (3.25 Å) and one longer (3.29 Å) Na–Si bond lengths. There are a spread of Na–P bond distances ranging from 2.98–3.40 Å. In the third Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four P+0.33- atoms. There are a spread of Na–P bond distances ranging from 2.92–3.28 Å. In the fourth Na1+ site, Na1+ is bonded to four P+0.33- atoms to form NaP4 tetrahedra that share corners with three equivalent SiNa2P4 tetrahedra, corners with five NaP4 tetrahedra, an edgeedge with one NaP4 tetrahedra, and an edgeedge with one SiNa2P4 tetrahedra. There are a spread of Na–P bond distances ranging from 2.86–2.92 Å. In the fifth Na1+ site, Na1+ is bonded to four P+0.33- atoms to form NaP4 tetrahedra that share corners with three equivalent NaP4 tetrahedra, corners with five equivalent SiNa2P4 tetrahedra, and edges with two NaP4 tetrahedra. There are a spread of Na–P bond distances ranging from 2.91–3.05 Å. Si4- is bonded to two equivalent Na1+ and four P+0.33- atoms to form distorted SiNa2P4 tetrahedra that share corners with eight NaP4 tetrahedra, an edgeedge with one NaP4 tetrahedra, and a faceface with one SiNa2P4 tetrahedra. There are a spread of Si–P bond distances ranging from 2.27–2.35 Å. There are three inequivalent P+0.33- sites. In the first P+0.33- site, P+0.33- is bonded in a 9-coordinate geometry to seven Na1+ and two equivalent Si4- atoms. In the second P+0.33- site, P+0.33- is bonded in a 9-coordinate geometry to eight Na1+ and one Si4- atom. In the third P+0.33- site, P+0.33- is bonded in a 7-coordinate geometry to seven Na1+ and one Si4- atom.