Materials Data on Na4SnTe4 by Materials Project

Abstract

Na4SnTe4 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of Na–Te bond distances ranging from 3.23–3.80 Å. In the second Na1+ site, Na1+ is bonded to five Te2- atoms to form distorted NaTe5 square pyramids that share corners with five NaTe6 octahedra, corners with four equivalent NaTe5 square pyramids, corners with three equivalent SnTe4 tetrahedra, an edgeedge with one NaTe6 octahedra, an edgeedge with one SnTe4 tetrahedra, and faces with two NaTe6 octahedra. The corner-sharing octahedra tilt angles range from 44–66°. There are a spread of Na–Te bond distances ranging from 3.12–3.69 Å. In the third Na1+ site, Na1+ is bonded to six Te2- atoms to form distorted NaTe6 octahedra that share corners with four equivalent NaTe6 octahedra, corners with three equivalent NaTe5 square pyramids, corners with four equivalent SnTe4 tetrahedra, edges with three equivalent NaTe6 octahedra, an edgeedge with one SnTe4 tetrahedra, a faceface with one NaTe6 octahedra, and a faceface with one NaTe5 square pyramid. The corner-sharing octahedra tilt angles range from 13–34°. There are a spread of Na–Te bond distances ranging from 3.19–3.75 Å. In the fourth Na1+ site, Na1+ is bonded to six Te2- atoms to form distorted NaTe6 octahedra that share corners with four equivalent NaTe6 octahedra, corners with two equivalent NaTe5 square pyramids, corners with four equivalent SnTe4 tetrahedra, edges with three equivalent NaTe6 octahedra, an edgeedge with one NaTe5 square pyramid, an edgeedge with one SnTe4 tetrahedra, a faceface with one NaTe6 octahedra, and a faceface with one NaTe5 square pyramid. The corner-sharing octahedra tilt angles range from 29–32°. There are a spread of Na–Te bond distances ranging from 3.17–3.80 Å. Sn4+ is bonded to four Te2- atoms to form SnTe4 tetrahedra that share corners with eight NaTe6 octahedra, corners with three equivalent NaTe5 square pyramids, edges with two NaTe6 octahedra, and an edgeedge with one NaTe5 square pyramid. The corner-sharing octahedra tilt angles range from 17–80°. There are two shorter (2.79 Å) and two longer (2.80 Å) Sn–Te bond lengths. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to five Na1+ and one Sn4+ atom to form distorted edge-sharing TeNa5Sn pentagonal pyramids. In the second Te2- site, Te2- is bonded in a 7-coordinate geometry to six Na1+ and one Sn4+ atom. In the third Te2- site, Te2- is bonded in a 7-coordinate geometry to six Na1+ and one Sn4+ atom. In the fourth Te2- site, Te2- is bonded in a 7-coordinate geometry to six Na1+ and one Sn4+ atom.