Materials Data on GdAgSe2 by Materials Project
GdAgSe2 crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. Gd3+ is bonded to six Se2- atoms to form GdSe6 octahedra that share corners with two equivalent AgSe6 octahedra, corners with four equivalent GdSe6 octahedra, edges with four equivalent GdSe6 octahedra, and edges with eight equivalent AgSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Gd–Se bond distances ranging from 2.87–2.94 Å. Ag1+ is bonded to six Se2- atoms to form distorted AgSe6 octahedra that share corners with two equivalent GdSe6 octahedra, corners with four equivalent AgSe6 octahedra, edges with four equivalent AgSe6 octahedra, and edges with eight equivalent GdSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–21°. There are a spread of Ag–Se bond distances ranging from 2.88–3.63 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to three equivalent Gd3+ and three equivalent Ag1+ atoms. In the second Se2- site, Se2- is bonded to three equivalent Gd3+ and three equivalent Ag1+ atoms to form a mixture of edge and corner-sharing SeGd3Ag3 octahedra. The corner-sharing octahedra tilt angles range from 6–8°.