MgTb4Ge4 is Magnesium tetraboride-derived structured and crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a 5-coordinate geometry to one Ge(2), two equivalent Ge(1), and two equivalent Ge(3) atoms. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to one Ge(1), two equivalent Ge(2), and three equivalent Ge(3) atoms. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to one Ge(2), two equivalent Ge(1), and four equivalent Ge(3) atoms. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Mg(1), two equivalent Tb(1), four equivalent Tb(2), and one Ge(2) atom. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to one Mg(1), two equivalent Tb(2), four equivalent Tb(1), and one Ge(1) atom. In the third Ge site, Ge(3) is bonded in a 9-coordinate geometry to one Mg(1), three equivalent Tb(1), four equivalent Tb(2), and one Ge(3) atom.
MgTb4Ge4 is Magnesium tetraboride-derived structured and crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a 5-coordinate geometry to one Ge(2), two equivalent Ge(1), and two equivalent Ge(3) atoms. The Mg(1)-Ge(2) bond length is 2.77 Å. There is one shorter (2.84 Å) and one longer (2.87 Å) Mg(1)-Ge(1) bond length. Both Mg(1)-Ge(3) bond lengths are 3.17 Å. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to one Ge(1), two equivalent Ge(2), and three equivalent Ge(3) atoms. The Tb(1)-Ge(1) bond length is 3.07 Å. There is one shorter (2.93 Å) and one longer (2.95 Å) Tb(1)-Ge(2) bond length. There are a spread of Tb(1)-Ge(3) bond distances ranging from 2.87-3.02 Å. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to one Ge(2), two equivalent Ge(1), and four equivalent Ge(3) atoms. The Tb(2)-Ge(2) bond length is 3.11 Å. There is one shorter (3.04 Å) and one longer (3.15 Å) Tb(2)-Ge(1) bond length. There are a spread of Tb(2)-Ge(3) bond distances ranging from 3.00-3.36 Å. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Mg(1), two equivalent Tb(1), four equivalent Tb(2), and one Ge(2) atom. The Ge(1)-Ge(2) bond length is 2.60 Å. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to one Mg(1), two equivalent Tb(2), four equivalent Tb(1), and one Ge(1) atom. In the third Ge site, Ge(3) is bonded in a 9-coordinate geometry to one Mg(1), three equivalent Tb(1), four equivalent Tb(2), and one Ge(3) atom. The Ge(3)-Ge(3) bond length is 2.72 Å.