Tm2Mn12GaGe11 crystallizes in the hexagonal P6mm space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one Ga(1), one Ge(7), and six equivalent Ge(2) atoms to form distorted TmGaGe7 hexagonal bipyramids that share  a cornercorner with one Ge(6)TmMn6Ga hexagonal bipyramid and edges with six equivalent Tm(1)GaGe7 hexagonal bipyramids. In the second Tm site, Tm(2) is bonded to one Ge(5), one Ge(6), and six equivalent Ge(1) atoms to form distorted edge-sharing TmGe8 hexagonal bipyramids. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Ga(1), two equivalent Ge(2), and two equivalent Ge(3) 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. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent Ge(1), two equivalent Ge(3), and two equivalent Ge(6) atoms. In the fourth Mn site, Mn(4) is bonded in a 6-coordinate geometry to two equivalent Ge(2), two equivalent Ge(4), and two equivalent Ge(7) atoms. Ga(1) is bonded in a 8-coordinate geometry to one Tm(1), six equivalent Mn(1), and one Ge(6) atom. There are seven inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to three equivalent Tm(2), three equivalent Mn(2), and three equivalent Mn(3) atoms. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to three equivalent Tm(1), three equivalent Mn(1), and three equivalent Mn(4) atoms. In the third Ge site, Ge(3) is bonded in a 6-coordinate geometry to three equivalent Mn(1) and three equivalent Mn(3) atoms. In the fourth Ge site, Ge(4) is bonded in a 6-coordinate geometry to three equivalent Mn(2) and three equivalent Mn(4) atoms. In the fifth Ge site, Ge(5) is bonded in a 8-coordinate geometry to one Tm(2), six equivalent Mn(2), and one Ge(7) atom. In the sixth Ge site, Ge(6) is bonded to one Tm(2), six equivalent Mn(3), and one Ga(1) atom to form distorted GeTmMn6Ga hexagonal bipyramids that share  a cornercorner with one Tm(1)GaGe7 hexagonal bipyramid and corners with six equivalent Ge(6)TmMn6Ga hexagonal bipyramids. In the seventh Ge site, Ge(7) is bonded in a 8-coordinate geometry to one Tm(1), six equivalent Mn(4), and one Ge(5) atom.
Tm2Mn12GaGe11 crystallizes in the hexagonal P6mm space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one Ga(1), one Ge(7), and six equivalent Ge(2) atoms to form distorted TmGaGe7 hexagonal bipyramids that share  a cornercorner with one Ge(6)TmMn6Ga hexagonal bipyramid and edges with six equivalent Tm(1)GaGe7 hexagonal bipyramids. The Tm(1)-Ga(1) bond length is 2.79 Å. The Tm(1)-Ge(7) bond length is 2.80 Å. All Tm(1)-Ge(2) bond lengths are 2.99 Å. In the second Tm site, Tm(2) is bonded to one Ge(5), one Ge(6), and six equivalent Ge(1) atoms to form distorted edge-sharing TmGe8 hexagonal bipyramids. The Tm(2)-Ge(5) bond length is 2.79 Å. The Tm(2)-Ge(6) bond length is 2.78 Å. All Tm(2)-Ge(1) bond lengths are 2.99 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Ga(1), two equivalent Ge(2), and two equivalent Ge(3) atoms. Both Mn(1)-Ga(1) bond lengths are 2.70 Å. Both Mn(1)-Ge(2) bond lengths are 2.50 Å. Both Mn(1)-Ge(3) bond lengths are 2.52 Å. 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 2.52 Å. Both Mn(2)-Ge(4) bond lengths are 2.52 Å. Both Mn(2)-Ge(5) bond lengths are 2.70 Å. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent Ge(1), two equivalent Ge(3), and two equivalent Ge(6) atoms. Both Mn(3)-Ge(1) bond lengths are 2.52 Å. Both Mn(3)-Ge(3) bond lengths are 2.54 Å. Both Mn(3)-Ge(6) bond lengths are 2.70 Å. In the fourth Mn site, Mn(4) is bonded in a 6-coordinate geometry to two equivalent Ge(2), two equivalent Ge(4), and two equivalent Ge(7) atoms. Both Mn(4)-Ge(2) bond lengths are 2.53 Å. Both Mn(4)-Ge(4) bond lengths are 2.52 Å. Both Mn(4)-Ge(7) bond lengths are 2.69 Å. Ga(1) is bonded in a 8-coordinate geometry to one Tm(1), six equivalent Mn(1), and one Ge(6) atom. The Ga(1)-Ge(6) bond length is 2.54 Å. There are seven inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to three equivalent Tm(2), three equivalent Mn(2), and three equivalent Mn(3) atoms. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to three equivalent Tm(1), three equivalent Mn(1), and three equivalent Mn(4) atoms. In the third Ge site, Ge(3) is bonded in a 6-coordinate geometry to three equivalent Mn(1) and three equivalent Mn(3) atoms. In the fourth Ge site, Ge(4) is bonded in a 6-coordinate geometry to three equivalent Mn(2) and three equivalent Mn(4) atoms. In the fifth Ge site, Ge(5) is bonded in a 8-coordinate geometry to one Tm(2), six equivalent Mn(2), and one Ge(7) atom. The Ge(5)-Ge(7) bond length is 2.55 Å. In the sixth Ge site, Ge(6) is bonded to one Tm(2), six equivalent Mn(3), and one Ga(1) atom to form distorted GeTmMn6Ga hexagonal bipyramids that share  a cornercorner with one Tm(1)GaGe7 hexagonal bipyramid and corners with six equivalent Ge(6)TmMn6Ga hexagonal bipyramids. In the seventh Ge site, Ge(7) is bonded in a 8-coordinate geometry to one Tm(1), six equivalent Mn(4), and one Ge(5) atom.