Materials Data on Ta3AgO8 by Materials Project

Abstract

Ta3AgO8 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. there are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to seven O2- atoms to form distorted TaO7 pentagonal bipyramids that share corners with two equivalent TaO8 hexagonal bipyramids, corners with two equivalent TaO7 pentagonal bipyramids, edges with two equivalent TaO8 hexagonal bipyramids, edges with four equivalent AgO8 hexagonal bipyramids, and edges with two equivalent TaO7 pentagonal bipyramids. There are a spread of Ta–O bond distances ranging from 1.96–2.30 Å. In the second Ta5+ site, Ta5+ is bonded to eight O2- atoms to form distorted TaO8 hexagonal bipyramids that share corners with four equivalent TaO7 pentagonal bipyramids, edges with two equivalent TaO8 hexagonal bipyramids, edges with two equivalent AgO8 hexagonal bipyramids, and edges with four equivalent TaO7 pentagonal bipyramids. There are four shorter (2.08 Å) and four longer (2.11 Å) Ta–O bond lengths. Ag1+ is bonded to eight O2- atoms to form distorted AgO8 hexagonal bipyramids that share edges with two equivalent TaO8 hexagonal bipyramids, edges with two equivalent AgO8 hexagonal bipyramids, and edges with eight equivalent TaO7 pentagonal bipyramids. There are four shorter (2.57 Å) and four longer (2.77 Å) Ag–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Ta5+ and one Ag1+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to three Ta5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ta5+ and two equivalent Ag1+ atoms.