Hf9Re4As crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 5-coordinate geometry to one Re(2), three equivalent Re(1), and one As(1) atom. In the second Hf site, Hf(2) is bonded in a distorted T-shaped geometry to two equivalent Re(1) and one As(1) atom. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded to two equivalent Hf(2), six equivalent Hf(1), two equivalent Re(1), and two equivalent Re(2) atoms to form distorted ReHf8Re4 cuboctahedra that share corners with four equivalent Re(1)Hf8Re4 cuboctahedra, faces with two equivalent Re(2)Hf6Re6 cuboctahedra, and faces with six equivalent Re(1)Hf8Re4 cuboctahedra. In the second Re site, Re(2) is bonded to six equivalent Hf(1) and six equivalent Re(1) atoms to form ReHf6Re6 cuboctahedra that share faces with two equivalent Re(2)Hf6Re6 cuboctahedra and faces with six equivalent Re(1)Hf8Re4 cuboctahedra. As(1) is bonded in a 9-coordinate geometry to three equivalent Hf(2) and six equivalent Hf(1) atoms.
Hf9Re4As crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 5-coordinate geometry to one Re(2), three equivalent Re(1), and one As(1) atom. The Hf(1)-Re(2) bond length is 2.89 Å. There is one shorter (2.84 Å) and two longer (3.02 Å) Hf(1)-Re(1) bond lengths. The Hf(1)-As(1) bond length is 2.72 Å. In the second Hf site, Hf(2) is bonded in a distorted T-shaped geometry to two equivalent Re(1) and one As(1) atom. Both Hf(2)-Re(1) bond lengths are 2.88 Å. The Hf(2)-As(1) bond length is 3.14 Å. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded to two equivalent Hf(2), six equivalent Hf(1), two equivalent Re(1), and two equivalent Re(2) atoms to form distorted ReHf8Re4 cuboctahedra that share corners with four equivalent Re(1)Hf8Re4 cuboctahedra, faces with two equivalent Re(2)Hf6Re6 cuboctahedra, and faces with six equivalent Re(1)Hf8Re4 cuboctahedra. Both Re(1)-Re(1) bond lengths are 2.85 Å. Both Re(1)-Re(2) bond lengths are 2.70 Å. In the second Re site, Re(2) is bonded to six equivalent Hf(1) and six equivalent Re(1) atoms to form ReHf6Re6 cuboctahedra that share faces with two equivalent Re(2)Hf6Re6 cuboctahedra and faces with six equivalent Re(1)Hf8Re4 cuboctahedra. As(1) is bonded in a 9-coordinate geometry to three equivalent Hf(2) and six equivalent Hf(1) atoms.