UFeAs2 is Parent of FeAs superconductors-derived structured and crystallizes in the tetragonal P4/nmm space group. U(1) is bonded to four equivalent Fe(1), four equivalent As(1), and four equivalent As(2) atoms to form distorted UFe4As8 cuboctahedra that share corners with four equivalent U(1)Fe4As8 cuboctahedra, corners with eight equivalent Fe(1)U4As4 tetrahedra, edges with eight equivalent U(1)Fe4As8 cuboctahedra, edges with four equivalent Fe(1)U4As4 tetrahedra, and faces with four equivalent U(1)Fe4As8 cuboctahedra. Fe(1) is bonded to four equivalent U(1) and four equivalent As(2) atoms to form distorted FeU4As4 tetrahedra that share corners with eight equivalent U(1)Fe4As8 cuboctahedra, edges with four equivalent U(1)Fe4As8 cuboctahedra, edges with four equivalent Fe(1)U4As4 tetrahedra, and faces with four equivalent Fe(1)U4As4 tetrahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent As(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent Fe(1) atoms.
UFeAs2 is Parent of FeAs superconductors-derived structured and crystallizes in the tetragonal P4/nmm space group. U(1) is bonded to four equivalent Fe(1), four equivalent As(1), and four equivalent As(2) atoms to form distorted UFe4As8 cuboctahedra that share corners with four equivalent U(1)Fe4As8 cuboctahedra, corners with eight equivalent Fe(1)U4As4 tetrahedra, edges with eight equivalent U(1)Fe4As8 cuboctahedra, edges with four equivalent Fe(1)U4As4 tetrahedra, and faces with four equivalent U(1)Fe4As8 cuboctahedra. All U(1)-Fe(1) bond lengths are 3.20 Å. All U(1)-As(1) bond lengths are 3.01 Å. All U(1)-As(2) bond lengths are 2.96 Å. Fe(1) is bonded to four equivalent U(1) and four equivalent As(2) atoms to form distorted FeU4As4 tetrahedra that share corners with eight equivalent U(1)Fe4As8 cuboctahedra, edges with four equivalent U(1)Fe4As8 cuboctahedra, edges with four equivalent Fe(1)U4As4 tetrahedra, and faces with four equivalent Fe(1)U4As4 tetrahedra. All Fe(1)-As(2) bond lengths are 2.52 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent As(1) atoms. All As(1)-As(1) bond lengths are 2.80 Å. In the second As site, As(2) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent Fe(1) atoms.