Tm3Ge4 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 8-coordinate geometry to two equivalent Ge(2), two equivalent Ge(3), and four equivalent Ge(1) atoms. In the second Tm site, Tm(2) is bonded in a 7-coordinate geometry to three equivalent Ge(2) and four equivalent Ge(1) atoms. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Tm(2), four equivalent Tm(1), one Ge(2), and two equivalent Ge(3) atoms. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to three equivalent Tm(2), four equivalent Tm(1), and two equivalent Ge(1) atoms. In the third Ge site, Ge(3) is bonded in a 4-coordinate geometry to four equivalent Tm(1) and four equivalent Ge(1) atoms.
Tm3Ge4 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 8-coordinate geometry to two equivalent Ge(2), two equivalent Ge(3), and four equivalent Ge(1) atoms. Both Tm(1)-Ge(2) bond lengths are 2.99 Å. Both Tm(1)-Ge(3) bond lengths are 2.99 Å. There are a spread of Tm(1)-Ge(1) bond distances ranging from 2.93-3.04 Å. In the second Tm site, Tm(2) is bonded in a 7-coordinate geometry to three equivalent Ge(2) and four equivalent Ge(1) atoms. There is one shorter (2.84 Å) and two longer (3.13 Å) Tm(2)-Ge(2) bond lengths. All Tm(2)-Ge(1) bond lengths are 2.92 Å. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Tm(2), four equivalent Tm(1), one Ge(2), and two equivalent Ge(3) atoms. The Ge(1)-Ge(2) bond length is 2.58 Å. Both Ge(1)-Ge(3) bond lengths are 2.82 Å. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to three equivalent Tm(2), four equivalent Tm(1), and two equivalent Ge(1) atoms. In the third Ge site, Ge(3) is bonded in a 4-coordinate geometry to four equivalent Tm(1) and four equivalent Ge(1) atoms.