HfCuSi2 is Parent of FeAs superconductors-derived structured and crystallizes in the tetragonal P4/nmm space group. Hf(1) is bonded to four equivalent Cu(1), four equivalent Si(1), and four equivalent Si(2) atoms to form distorted HfCu4Si8 cuboctahedra that share corners with four equivalent Hf(1)Cu4Si8 cuboctahedra, edges with eight equivalent Hf(1)Cu4Si8 cuboctahedra, edges with eight equivalent Cu(1)Hf4Cu4Si4 cuboctahedra, faces with four equivalent Hf(1)Cu4Si8 cuboctahedra, and faces with four equivalent Cu(1)Hf4Cu4Si4 cuboctahedra. Cu(1) is bonded to four equivalent Hf(1), four equivalent Cu(1), and four equivalent Si(2) atoms to form CuHf4Cu4Si4 cuboctahedra that share corners with four equivalent Cu(1)Hf4Cu4Si4 cuboctahedra, edges with eight equivalent Hf(1)Cu4Si8 cuboctahedra, faces with four equivalent Hf(1)Cu4Si8 cuboctahedra, and faces with eight equivalent Cu(1)Hf4Cu4Si4 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Hf(1) and four equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to four equivalent Hf(1) and four equivalent Cu(1) atoms.
HfCuSi2 is Parent of FeAs superconductors-derived structured and crystallizes in the tetragonal P4/nmm space group. Hf(1) is bonded to four equivalent Cu(1), four equivalent Si(1), and four equivalent Si(2) atoms to form distorted HfCu4Si8 cuboctahedra that share corners with four equivalent Hf(1)Cu4Si8 cuboctahedra, edges with eight equivalent Hf(1)Cu4Si8 cuboctahedra, edges with eight equivalent Cu(1)Hf4Cu4Si4 cuboctahedra, faces with four equivalent Hf(1)Cu4Si8 cuboctahedra, and faces with four equivalent Cu(1)Hf4Cu4Si4 cuboctahedra. All Hf(1)-Cu(1) bond lengths are 3.01 Å. All Hf(1)-Si(1) bond lengths are 2.79 Å. All Hf(1)-Si(2) bond lengths are 2.73 Å. Cu(1) is bonded to four equivalent Hf(1), four equivalent Cu(1), and four equivalent Si(2) atoms to form CuHf4Cu4Si4 cuboctahedra that share corners with four equivalent Cu(1)Hf4Cu4Si4 cuboctahedra, edges with eight equivalent Hf(1)Cu4Si8 cuboctahedra, faces with four equivalent Hf(1)Cu4Si8 cuboctahedra, and faces with eight equivalent Cu(1)Hf4Cu4Si4 cuboctahedra. All Cu(1)-Cu(1) bond lengths are 2.59 Å. All Cu(1)-Si(2) bond lengths are 2.38 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Hf(1) and four equivalent Si(1) atoms. All Si(1)-Si(1) bond lengths are 2.59 Å. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to four equivalent Hf(1) and four equivalent Cu(1) atoms.