Search NASA⌕ Search

SEARCH · Search NASA

Results for “Ho2Be2SiO7”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

Materials Data on Ho2Be2SiO7 by Materials Project

Be2Ho2SiO7 crystallizes in the tetragonal P-42_1m space group. The structure is three-dimensional. Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one BeO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.57–1.70 Å. Ho3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ho–O bond distances ranging from 2.26–2.64 Å. Si4+ is bonded to four equivalent O2- atoms to form SiO4 tetrahedra that share corners with four equivalent BeO4 tetrahedra. All Si–O bond lengths are 1.64 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to one Be2+ and three equivalent Ho3+ atoms to form a mixture of distorted edge and corner-sharing OHo3Be tetrahedra. In the second O2- site, O2- is bonded to two equivalent Be2+ and two equivalent Ho3+ atoms to form a mixture of distorted edge and corner-sharing OHo2Be2 tetrahedra. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Be2+, two equivalent Ho3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗