The compound described by Tb2AlGe3 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 11-coordinate geometry to two equivalent Al(1), one Ge(1), four equivalent Ge(2), and four equivalent Ge(3) atoms. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to two equivalent Ge(2), two equivalent Ge(3), and three equivalent Ge(1) atoms. Al(1) is bonded to two equivalent Tb(1), one Ge(2), and three equivalent Ge(1) atoms to form distorted AlTb2Ge4 tetrahedra that share corners with two equivalent Ge(1)Tb4Al3 pentagonal bipyramids and edges with four equivalent Al(1)Tb2Ge4 tetrahedra. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one Tb(1), three equivalent Tb(2), and three equivalent Al(1) atoms to form distorted GeTb4Al3 pentagonal bipyramids that share corners with two equivalent Al(1)Tb2Ge4 tetrahedra and edges with six equivalent Ge(1)Tb4Al3 pentagonal bipyramids. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), one Al(1), and two equivalent Ge(3) atoms. In the third Ge site, Ge(3) is bonded in a 8-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), and two equivalent Ge(2) atoms. is represented by the CIF file [CIF]
data_Tb2AlGe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.235
_cell_length_b   6.809
_cell_length_c   17.827
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   514.031
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Tb  Tb0  1  0.750  0.331  0.296  1.0
  Tb  Tb1  1  0.750  0.328  0.085  1.0
  Tb  Tb2  1  0.250  0.672  0.915  1.0
  Tb  Tb3  1  0.250  0.169  0.796  1.0
  Tb  Tb4  1  0.750  0.828  0.415  1.0
  Tb  Tb5  1  0.750  0.831  0.204  1.0
  Tb  Tb6  1  0.250  0.172  0.585  1.0
  Tb  Tb7  1  0.250  0.669  0.704  1.0
  Al  Al8  1  0.750  0.550  0.565  1.0
  Al  Al9  1  0.250  0.950  0.065  1.0
  Al  Al10  1  0.750  0.050  0.935  1.0
  Al  Al11  1  0.250  0.450  0.435  1.0
  Ge  Ge12  1  0.750  0.252  0.465  1.0
  Ge  Ge13  1  0.250  0.145  0.188  1.0
  Ge  Ge14  1  0.750  0.855  0.812  1.0
  Ge  Ge15  1  0.750  0.355  0.688  1.0
  Ge  Ge16  1  0.750  0.467  0.827  1.0
  Ge  Ge17  1  0.250  0.033  0.327  1.0
  Ge  Ge18  1  0.750  0.967  0.673  1.0
  Ge  Ge19  1  0.250  0.645  0.312  1.0
  Ge  Ge20  1  0.250  0.748  0.535  1.0
  Ge  Ge21  1  0.250  0.533  0.173  1.0
  Ge  Ge22  1  0.750  0.752  0.035  1.0
  Ge  Ge23  1  0.250  0.248  0.965  1.0
[/CIF]
.
The compound described by Tb2AlGe3 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 11-coordinate geometry to two equivalent Al(1), one Ge(1), four equivalent Ge(2), and four equivalent Ge(3) atoms. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to two equivalent Ge(2), two equivalent Ge(3), and three equivalent Ge(1) atoms. Al(1) is bonded to two equivalent Tb(1), one Ge(2), and three equivalent Ge(1) atoms to form distorted AlTb2Ge4 tetrahedra that share corners with two equivalent Ge(1)Tb4Al3 pentagonal bipyramids and edges with four equivalent Al(1)Tb2Ge4 tetrahedra. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one Tb(1), three equivalent Tb(2), and three equivalent Al(1) atoms to form distorted GeTb4Al3 pentagonal bipyramids that share corners with two equivalent Al(1)Tb2Ge4 tetrahedra and edges with six equivalent Ge(1)Tb4Al3 pentagonal bipyramids. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), one Al(1), and two equivalent Ge(3) atoms. In the third Ge site, Ge(3) is bonded in a 8-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), and two equivalent Ge(2) atoms. is represented by the CIF file [CIF]
data_Tb2AlGe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.235
_cell_length_b   6.809
_cell_length_c   17.827
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   514.031
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Tb  Tb0  1  0.750  0.331  0.296  1.0
  Tb  Tb1  1  0.750  0.328  0.085  1.0
  Tb  Tb2  1  0.250  0.672  0.915  1.0
  Tb  Tb3  1  0.250  0.169  0.796  1.0
  Tb  Tb4  1  0.750  0.828  0.415  1.0
  Tb  Tb5  1  0.750  0.831  0.204  1.0
  Tb  Tb6  1  0.250  0.172  0.585  1.0
  Tb  Tb7  1  0.250  0.669  0.704  1.0
  Al  Al8  1  0.750  0.550  0.565  1.0
  Al  Al9  1  0.250  0.950  0.065  1.0
  Al  Al10  1  0.750  0.050  0.935  1.0
  Al  Al11  1  0.250  0.450  0.435  1.0
  Ge  Ge12  1  0.750  0.252  0.465  1.0
  Ge  Ge13  1  0.250  0.145  0.188  1.0
  Ge  Ge14  1  0.750  0.855  0.812  1.0
  Ge  Ge15  1  0.750  0.355  0.688  1.0
  Ge  Ge16  1  0.750  0.467  0.827  1.0
  Ge  Ge17  1  0.250  0.033  0.327  1.0
  Ge  Ge18  1  0.750  0.967  0.673  1.0
  Ge  Ge19  1  0.250  0.645  0.312  1.0
  Ge  Ge20  1  0.250  0.748  0.535  1.0
  Ge  Ge21  1  0.250  0.533  0.173  1.0
  Ge  Ge22  1  0.750  0.752  0.035  1.0
  Ge  Ge23  1  0.250  0.248  0.965  1.0
[/CIF]
.