Materials Data on SrCu4Ag by Materials Project
SrAgCu4 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Sr is bonded in a 10-coordinate geometry to four equivalent Ag and fourteen Cu atoms. All Sr–Ag bond lengths are 3.27 Å. There are a spread of Sr–Cu bond distances ranging from 3.04–3.47 Å. Ag is bonded to four equivalent Sr and eight Cu atoms to form AgSr4Cu8 cuboctahedra that share corners with eight equivalent AgSr4Cu8 cuboctahedra, corners with eight equivalent CuSr4Cu6Ag2 cuboctahedra, edges with two equivalent AgSr4Cu8 cuboctahedra, edges with eight equivalent CuSr4Cu6Ag2 cuboctahedra, faces with two equivalent AgSr4Cu8 cuboctahedra, and faces with eight equivalent CuSr4Cu6Ag2 cuboctahedra. There are four shorter (2.77 Å) and four longer (2.82 Å) Ag–Cu bond lengths. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a 11-coordinate geometry to three equivalent Sr, two equivalent Ag, and six Cu atoms. There are four shorter (2.50 Å) and two longer (2.76 Å) Cu–Cu bond lengths. In the second Cu site, Cu is bonded to four equivalent Sr, two equivalent Ag, and six Cu atoms to form CuSr4Cu6Ag2 cuboctahedra that share corners with four equivalent AgSr4Cu8 cuboctahedra, corners with twelve equivalent CuSr4Cu6Ag2 cuboctahedra, edges with four equivalent AgSr4Cu8 cuboctahedra, edges with six equivalent CuSr4Cu6Ag2 cuboctahedra, faces with four equivalent AgSr4Cu8 cuboctahedra, and faces with six equivalent CuSr4Cu6Ag2 cuboctahedra. Both Cu–Cu bond lengths are 2.51 Å.