Hf2Nb3Ge4 crystallizes in the orthorhombic Pnma space group. Hf(1) is bonded in a 7-coordinate geometry to one Ge(2), two equivalent Ge(3), and four equivalent Ge(1) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one Ge(3), two equivalent Ge(2), and three equivalent Ge(1) atoms. In the second Nb site, Nb(2) is bonded to two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms to form distorted corner-sharing NbGe6 octahedra. The corner-sharing octahedral tilt angles range from 45-56°. There are three inequivalent Ge sites. In the first Ge site, Ge(3) is bonded in a 9-coordinate geometry to four equivalent Hf(1), two equivalent Nb(1), two equivalent Nb(2), and one Ge(2) atom. In the second Ge site, Ge(1) is bonded in a 8-coordinate geometry to four equivalent Hf(1), one Nb(2), and three equivalent Nb(1) atoms. In the third Ge site, Ge(2) is bonded in a 9-coordinate geometry to two equivalent Hf(1), two equivalent Nb(2), four equivalent Nb(1), and one Ge(3) atom.
Hf2Nb3Ge4 crystallizes in the orthorhombic Pnma space group. Hf(1) is bonded in a 7-coordinate geometry to one Ge(2), two equivalent Ge(3), and four equivalent Ge(1) atoms. The Hf(1)-Ge(2) bond length is 2.90 Å. There is one shorter (2.80 Å) and one longer (2.91 Å) Hf(1)-Ge(3) bond length. There are a spread of Hf(1)-Ge(1) bond distances ranging from 2.76-2.95 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one Ge(3), two equivalent Ge(2), and three equivalent Ge(1) atoms. The Nb(1)-Ge(3) bond length is 2.77 Å. There is one shorter (2.64 Å) and one longer (2.67 Å) Nb(1)-Ge(2) bond length. There are a spread of Nb(1)-Ge(1) bond distances ranging from 2.57-2.73 Å. In the second Nb site, Nb(2) is bonded to two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms to form distorted corner-sharing NbGe6 octahedra. The corner-sharing octahedral tilt angles range from 45-56°. Both Nb(2)-Ge(1) bond lengths are 2.79 Å. There is one shorter (2.65 Å) and one longer (2.79 Å) Nb(2)-Ge(2) bond length. There is one shorter (2.65 Å) and one longer (2.67 Å) Nb(2)-Ge(3) bond length. There are three inequivalent Ge sites. In the first Ge site, Ge(3) is bonded in a 9-coordinate geometry to four equivalent Hf(1), two equivalent Nb(1), two equivalent Nb(2), and one Ge(2) atom. The Ge(3)-Ge(2) bond length is 2.57 Å. In the second Ge site, Ge(1) is bonded in a 8-coordinate geometry to four equivalent Hf(1), one Nb(2), and three equivalent Nb(1) atoms. In the third Ge site, Ge(2) is bonded in a 9-coordinate geometry to two equivalent Hf(1), two equivalent Nb(2), four equivalent Nb(1), and one Ge(3) atom.