Materials Data on Lu2Si2O7 by Materials Project
Lu2Si2O7 crystallizes in the tetragonal P4_12_12 space group. The structure is three-dimensional. Lu3+ is bonded to seven O2- atoms to form distorted LuO7 pentagonal bipyramids that share corners with five equivalent SiO4 tetrahedra, edges with five equivalent LuO7 pentagonal bipyramids, and an edgeedge with one SiO4 tetrahedra. There are a spread of Lu–O bond distances ranging from 2.16–2.50 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with five equivalent LuO7 pentagonal bipyramids, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one LuO7 pentagonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.68 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Lu3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Lu3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Lu3+ and one Si4+ atom.