DOE OSTI2020
Pd2CuSn crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. there are five inequivalent Pd sites. In the first Pd site, Pd is bonded to eight Pd and four equivalent Sn atoms to form distorted PdSn4Pd8 cuboctahedra that share corners with four equivalent PdCu4Sn4Pd4 cuboctahedra, corners with eight CuSn4Pd8 cuboctahedra, edges with eight equivalent PdCu4Sn4Pd4 cuboctahedra, edges with eight equivalent CuCu2Sn4Pd6 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, faces with four CuSn4Pd8 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, and faces with ten PdSn4Pd8 cuboctahedra. There are four shorter (2.83 Å) and four longer (2.94 Å) Pd–Pd bond lengths. All Pd–Sn bond lengths are 2.82 Å. In the second Pd site, Pd is bonded to four Pd, four Cu, and four equivalent Sn atoms to form PdCu4Sn4Pd4 cuboctahedra that share corners with twelve PdCu4Sn4Pd4 cuboctahedra, edges with eight PdSn4Pd8 cuboctahedra, edges with eight CuCu4Sn4Pd4 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, faces with four CuSn4Pd8 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, and faces with ten PdCu4Sn4Pd4 cuboctahedra. There are two shorter (2.81 Å) and two longer (2.82 Å) Pd–Pd bond lengths. There are two shorter (2.80 Å) and two longer (2.85 Å) Pd–Cu bond lengths. All Pd–Sn bond lengths are 2.81 Å. In the third Pd site, Pd is bonded to six Pd, two equivalent Cu, and four equivalent Sn atoms to form distorted PdCu2Sn4Pd6 cuboctahedra that share corners with four equivalent PdCu2Sn4Pd6 cuboctahedra, corners with eight equivalent CuCu2Sn4Pd6 cuboctahedra, edges with four equivalent CuCu4Sn4Pd4 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, edges with twelve PdCu4Sn4Pd4 cuboctahedra, faces with four CuSn4Pd8 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, and faces with ten PdSn4Pd8 cuboctahedra. Both Pd–Pd bond lengths are 2.97 Å. Both Pd–Cu bond lengths are 2.78 Å. All Pd–Sn bond lengths are 2.82 Å. In the fourth Pd site, Pd is bonded to four equivalent Pd, four equivalent Cu, and four equivalent Sn atoms to form PdCu4Sn4Pd4 cuboctahedra that share corners with four equivalent PdSn4Pd8 cuboctahedra, corners with eight CuSn4Pd8 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, edges with sixteen PdCu2Sn4Pd6 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, faces with six PdCu4Sn4Pd4 cuboctahedra, and faces with eight CuSn4Pd8 cuboctahedra. All Pd–Cu bond lengths are 2.80 Å. All Pd–Sn bond lengths are 2.84 Å. In the fifth Pd site, Pd is bonded to four Pd, four Cu, and four equivalent Sn atoms to form distorted PdCu4Sn4Pd4 cuboctahedra that share corners with twelve PdCu4Sn4Pd4 cuboctahedra, edges with eight PdCu2Sn4Pd6 cuboctahedra, edges with eight CuSn4Pd8 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, faces with four CuCu4Sn4Pd4 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, and faces with ten PdSn4Pd8 cuboctahedra. There are two shorter (2.71 Å) and two longer (2.72 Å) Pd–Cu bond lengths. All Pd–Sn bond lengths are 2.81 Å. There are three inequivalent Cu sites. In the first Cu site, Cu is bonded to eight Pd and four equivalent Sn atoms to form CuSn4Pd8 cuboctahedra that share corners with four equivalent CuCu4Sn4Pd4 cuboctahedra, corners with eight PdSn4Pd8 cuboctahedra, edges with eight equivalent PdCu4Sn4Pd4 cuboctahedra, edges with eight equivalent CuCu2Sn4Pd6 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, faces with two equivalent CuSn4Pd8 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, and faces with twelve PdSn4Pd8 cuboctahedra. All Cu–Sn bond lengths are 2.82 Å. In the second Cu site, Cu is bonded to four equivalent Pd, four equivalent Cu, and four equivalent Sn atoms to form distorted CuCu4Sn4Pd4 cuboctahedra that share corners with four equivalent CuSn4Pd8 cuboctahedra, corners with eight PdSn4Pd8 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, edges with sixteen PdCu4Sn4Pd4 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, faces with six CuCu4Sn4Pd4 cuboctahedra, and faces with eight PdSn4Pd8 cuboctahedra. All Cu–Cu bond lengths are 2.81 Å. All Cu–Sn bond lengths are 2.84 Å. In the third Cu site, Cu is bonded to six Pd, two equivalent Cu, and four equivalent Sn atoms to form distorted CuCu2Sn4Pd6 cuboctahedra that share corners with four equivalent CuCu2Sn4Pd6 cuboctahedra, corners with eight equivalent PdCu2Sn4Pd6 cuboctahedra, edges with four equivalent CuSn4Pd8 cuboctahedra, edges with eight equivalent SnCu4Pd8 cuboctahedra, edges with twelve PdSn4Pd8 cuboctahedra, faces with four equivalent SnCu4Pd8 cuboctahedra, faces with six CuCu4Sn4Pd4 cuboctahedra, and faces with eight PdCu4Sn4Pd4 cuboctahedra. All Cu–Sn bond lengths are 2.84 Å. Sn is bonded to eight Pd and four Cu atoms to form SnCu4Pd8 cuboctahedra that share corners with twelve equivalent SnCu4Pd8 cuboctahedra, edges with eight CuSn4Pd8 cuboctahedra, edges with sixteen PdSn4Pd8 cuboctahedra, faces with four CuSn4Pd8 cuboctahedra, faces with six equivalent SnCu4Pd8 cuboctahedra, and faces with eight PdSn4Pd8 cuboctahedra.