TbMn2Si2 crystallizes in the tetragonal I4/mmm space group. Tb(1) is bonded in a 16-coordinate geometry to eight equivalent Mn(1) and eight equivalent Si(1) atoms. Mn(1) is bonded to four equivalent Tb(1) and four equivalent Si(1) atoms to form a mixture of edge, corner, and face-sharing MnTb4Si4 tetrahedra. Si(1) is bonded in a 9-coordinate geometry to four equivalent Tb(1), four equivalent Mn(1), and one Si(1) atom.
TbMn2Si2 crystallizes in the tetragonal I4/mmm space group. Tb(1) is bonded in a 16-coordinate geometry to eight equivalent Mn(1) and eight equivalent Si(1) atoms. All Tb(1)-Mn(1) bond lengths are 3.27 Å. All Tb(1)-Si(1) bond lengths are 3.01 Å. Mn(1) is bonded to four equivalent Tb(1) and four equivalent Si(1) atoms to form a mixture of edge, corner, and face-sharing MnTb4Si4 tetrahedra. All Mn(1)-Si(1) bond lengths are 2.39 Å. Si(1) is bonded in a 9-coordinate geometry to four equivalent Tb(1), four equivalent Mn(1), and one Si(1) atom. The Si(1)-Si(1) bond length is 2.47 Å.