Materials Data on Na4SeO5 by Materials Project
Na4SeO5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, corners with two equivalent SeO5 trigonal bipyramids, edges with nine NaO6 octahedra, an edgeedge with one SeO5 square pyramid, and an edgeedge with one SeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 12–33°. There are a spread of Na–O bond distances ranging from 2.34–2.80 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, a cornercorner with one SeO5 square pyramid, a cornercorner with one SeO5 trigonal bipyramid, edges with nine NaO6 octahedra, and edges with two equivalent SeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 11–36°. There are a spread of Na–O bond distances ranging from 2.40–2.78 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four NaO6 octahedra, corners with two equivalent SeO5 square pyramids, edges with ten NaO6 octahedra, and edges with two equivalent SeO5 square pyramids. The corner-sharing octahedra tilt angles range from 12–21°. There are a spread of Na–O bond distances ranging from 2.32–2.93 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with four NaO6 octahedra, corners with four equivalent SeO5 square pyramids, corners with two equivalent SeO5 trigonal bipyramids, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 33–36°. There are a spread of Na–O bond distances ranging from 2.40–2.77 Å. In the fifth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six NaO6 octahedra, edges with nine NaO6 octahedra, edges with two equivalent SeO5 square pyramids, and an edgeedge with one SeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 10–28°. There are a spread of Na–O bond distances ranging from 2.34–2.46 Å. In the sixth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six NaO6 octahedra, a cornercorner with one SeO5 square pyramid, a cornercorner with one SeO5 trigonal bipyramid, edges with eight NaO6 octahedra, an edgeedge with one SeO5 square pyramid, and an edgeedge with one SeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 24–35°. There are a spread of Na–O bond distances ranging from 2.32–2.56 Å. In the seventh Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, corners with two equivalent SeO5 trigonal bipyramids, edges with nine NaO6 octahedra, and edges with two equivalent SeO5 square pyramids. The corner-sharing octahedra tilt angles range from 10–34°. There are a spread of Na–O bond distances ranging from 2.29–2.91 Å. In the eighth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four NaO6 octahedra, corners with two equivalent SeO5 square pyramids, edges with ten NaO6 octahedra, and edges with two equivalent SeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–27°. There are a spread of Na–O bond distances ranging from 2.29–2.85 Å. In the ninth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, a cornercorner with one SeO5 square pyramid, a cornercorner with one SeO5 trigonal bipyramid, edges with nine NaO6 octahedra, an edgeedge with one SeO5 square pyramid, and an edgeedge with one SeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 21–35°. There are a spread of Na–O bond distances ranging from 2.33–2.64 Å. There are two inequivalent Se6+ sites. In the first Se6+ site, Se6+ is bonded to five O2- atoms to form SeO5 trigonal bipyramids that share corners with eight NaO6 octahedra and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 3–72°. There are a spread of Se–O bond distances ranging from 1.74–1.82 Å. In the second Se6+ site, Se6+ is bonded to five O2- atoms to form SeO5 square pyramids that share corners with eight NaO6 octahedra and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 2–72°. There are a spread of Se–O bond distances ranging from 1.75–1.83 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Se6+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Se6+ atom. In the third O2- site, O2- is bonded to five Na1+ and one Se6+ atom to form ONa5Se octahedra that share a cornercorner with one ONa5Se octahedra, a cornercorner with one ONa4Se trigonal bipyramid, an edgeedge with one ONa5Se octahedra, and an edgeedge with one ONa4Se trigonal bipyramid. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Se6+ atom. In the fifth O2- site, O2- is bonded to four Na1+ and one Se6+ atom to form distorted ONa4Se trigonal bipyramids that share corners with four ONa4Se trigonal bipyramids and edges with two equivalent ONa5Se octahedra. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Se6+ atom. In the seventh O2- site, O2- is bonded to five Na1+ and one Se6+ atom to form distorted ONa5Se octahedra that share edges with two ONa5Se octahedra and edges with two equivalent ONa4Se trigonal bipyramids. In the eighth O2- site, O2- is bonded to four Na1+ and one Se6+ atom to form distorted ONa4Se trigonal bipyramids that share a cornercorner with one ONa5Se octahedra, corners with four ONa4Se trigonal bipyramids, and an edgeedge with one ONa5Se octahedra. The corner-sharing octahedral tilt angles are 19°. In the ninth O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Se6+ atom. In the tenth O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Se6+ atom.