Materials Data on Na3HoSi2O7 by Materials Project

Dataset · Wed Apr 29 04:00:00 EDT 2020

DOI:https://doi.org/10.17188/1666878· OSTI ID:1666878

Na3HoSi2O7 crystallizes in the hexagonal P6_3/m 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 equivalent O2- atoms. All Na–O bond lengths are 2.58 Å. In the second Na1+ site, Na1+ is bonded to six equivalent O2- atoms to form distorted NaO6 pentagonal pyramids that share corners with six equivalent NaO4 tetrahedra, corners with six equivalent SiO4 tetrahedra, and faces with two equivalent HoO6 octahedra. All Na–O bond lengths are 2.53 Å. In the third Na1+ site, Na1+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All Na–O bond lengths are 2.29 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share a cornercorner with one HoO6 octahedra, a cornercorner with one NaO6 pentagonal pyramid, a cornercorner with one HoO6 pentagonal pyramid, corners with two equivalent NaO4 tetrahedra, corners with four equivalent SiO4 tetrahedra, and an edgeedge with one HoO6 octahedra. The corner-sharing octahedral tilt angles are 76°. There are a spread of Na–O bond distances ranging from 2.32–2.54 Å. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six equivalent O2- atoms to form distorted HoO6 pentagonal pyramids that share corners with six equivalent NaO4 tetrahedra and corners with six equivalent SiO4 tetrahedra. All Ho–O bond lengths are 2.29 Å. In the second Ho3+ site, Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with three equivalent NaO4 tetrahedra, corners with six equivalent SiO4 tetrahedra, edges with three equivalent NaO4 tetrahedra, and a faceface with one NaO6 pentagonal pyramid. There are three shorter (2.24 Å) and three longer (2.27 Å) Ho–O bond lengths. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent HoO6 octahedra, a cornercorner with one NaO6 pentagonal pyramid, a cornercorner with one HoO6 pentagonal pyramid, a cornercorner with one SiO4 tetrahedra, and corners with four equivalent NaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–38°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Ho3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to one Na1+ and two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ho3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ho3+, and one Si4+ atom.

• Research Organization: LBNL Materials Project; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Contributing Organization: The Materials Project; MIT; UC Berkeley; Duke; U Louvain
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1666878
• Report Number(s): mp-1195700
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Ho-Na-O-Si
Na3HoSi2O7
crystal structure