HfMnGe2 crystallizes in the orthorhombic Pbam space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 8-coordinate geometry to one Ge(4), one Ge(5), two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms. In the second Hf site, Hf(2) is bonded to two equivalent Ge(1), two equivalent Ge(3), and three equivalent Ge(5) atoms to form a mixture of distorted corner and edge-sharing HfGe7 pentagonal bipyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to one Ge(2), one Ge(3), one Ge(4), one Ge(5), and two equivalent Ge(1) atoms. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent Ge(1), two equivalent Ge(4), and two equivalent Ge(5) atoms. There are five inequivalent Ge sites. In the first Ge site, Ge(2) is bonded in a 7-coordinate geometry to four equivalent Hf(1), two equivalent Mn(1), and one Ge(2) atom. In the second Ge site, Ge(3) is bonded in a 9-coordinate geometry to two equivalent Hf(2), four equivalent Hf(1), two equivalent Mn(1), and one Ge(3) atom. In the third Ge site, Ge(4) is bonded in a 6-coordinate geometry to two equivalent Hf(1), two equivalent Mn(1), and two equivalent Mn(2) atoms. In the fourth Ge site, Ge(5) is bonded in a 9-coordinate geometry to two equivalent Hf(1), three equivalent Hf(2), two equivalent Mn(1), and two equivalent Mn(2) atoms. In the fifth Ge site, Ge(1) is bonded in a 7-coordinate geometry to one Hf(2), two equivalent Hf(1), one Mn(2), two equivalent Mn(1), and one Ge(1) atom.
HfMnGe2 crystallizes in the orthorhombic Pbam space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 8-coordinate geometry to one Ge(4), one Ge(5), two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms. The Hf(1)-Ge(4) bond length is 2.80 Å. The Hf(1)-Ge(5) bond length is 2.75 Å. Both Hf(1)-Ge(1) bond lengths are 2.89 Å. There is one shorter (2.90 Å) and one longer (2.91 Å) Hf(1)-Ge(2) bond length. There is one shorter (2.86 Å) and one longer (2.88 Å) Hf(1)-Ge(3) bond length. In the second Hf site, Hf(2) is bonded to two equivalent Ge(1), two equivalent Ge(3), and three equivalent Ge(5) atoms to form a mixture of distorted corner and edge-sharing HfGe7 pentagonal bipyramids. Both Hf(2)-Ge(1) bond lengths are 2.75 Å. Both Hf(2)-Ge(3) bond lengths are 2.83 Å. There are two shorter (2.90 Å) and one longer (2.93 Å) Hf(2)-Ge(5) bond length. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to one Ge(2), one Ge(3), one Ge(4), one Ge(5), and two equivalent Ge(1) atoms. The Mn(1)-Ge(2) bond length is 2.47 Å. The Mn(1)-Ge(3) bond length is 2.48 Å. The Mn(1)-Ge(4) bond length is 2.58 Å. The Mn(1)-Ge(5) bond length is 2.56 Å. There is one shorter (2.54 Å) and one longer (2.55 Å) Mn(1)-Ge(1) bond length. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent Ge(1), two equivalent Ge(4), and two equivalent Ge(5) atoms. Both Mn(2)-Ge(1) bond lengths are 2.56 Å. Both Mn(2)-Ge(4) bond lengths are 2.55 Å. Both Mn(2)-Ge(5) bond lengths are 2.54 Å. There are five inequivalent Ge sites. In the first Ge site, Ge(2) is bonded in a 7-coordinate geometry to four equivalent Hf(1), two equivalent Mn(1), and one Ge(2) atom. The Ge(2)-Ge(2) bond length is 2.48 Å. In the second Ge site, Ge(3) is bonded in a 9-coordinate geometry to two equivalent Hf(2), four equivalent Hf(1), two equivalent Mn(1), and one Ge(3) atom. The Ge(3)-Ge(3) bond length is 2.51 Å. In the third Ge site, Ge(4) is bonded in a 6-coordinate geometry to two equivalent Hf(1), two equivalent Mn(1), and two equivalent Mn(2) atoms. In the fourth Ge site, Ge(5) is bonded in a 9-coordinate geometry to two equivalent Hf(1), three equivalent Hf(2), two equivalent Mn(1), and two equivalent Mn(2) atoms. In the fifth Ge site, Ge(1) is bonded in a 7-coordinate geometry to one Hf(2), two equivalent Hf(1), one Mn(2), two equivalent Mn(1), and one Ge(1) atom. The Ge(1)-Ge(1) bond length is 2.51 Å.