The crystal structure described by BaTb2Mn2O7 crystallizes in the monoclinic C2/m space group. Ba(1) is bonded in a 12-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(4), two equivalent O(6), and four equivalent O(5) atoms. Tb(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), one O(6), and three equivalent O(3) atoms. Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 5-27°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms to form distorted OBa2Tb2Mn2 octahedra that share corners with two equivalent O(6)Ba2Tb2Mn2 octahedra, corners with four equivalent O(5)Ba4Mn2 octahedra,  an edgeedge with one O(2)Ba2Tb2Mn2 octahedra, faces with two equivalent O(6)Ba2Tb2Mn2 octahedra, and faces with two equivalent O(5)Ba4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. In the third O site, O(3) is bonded in a 4-coordinate geometry to three equivalent Tb(1) and one Mn(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms. In the fifth O site, O(5) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form distorted OBa4Mn2 octahedra that share corners with four equivalent O(2)Ba2Tb2Mn2 octahedra, corners with four equivalent O(6)Ba2Tb2Mn2 octahedra, corners with four equivalent O(5)Ba4Mn2 octahedra, edges with four equivalent O(5)Ba4Mn2 octahedra, faces with two equivalent O(2)Ba2Tb2Mn2 octahedra, and faces with two equivalent O(6)Ba2Tb2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 4-63°. In the sixth O site, O(6) is bonded to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms to form distorted OBa2Tb2Mn2 octahedra that share corners with two equivalent O(2)Ba2Tb2Mn2 octahedra, corners with four equivalent O(5)Ba4Mn2 octahedra,  an edgeedge with one O(6)Ba2Tb2Mn2 octahedra, faces with two equivalent O(2)Ba2Tb2Mn2 octahedra, and faces with two equivalent O(5)Ba4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 57-63°. is represented by the CIF file [CIF]
data_BaTb2Mn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.357
_cell_length_b   10.357
_cell_length_c   5.603
_cell_angle_alpha   89.998
_cell_angle_beta   89.998
_cell_angle_gamma   148.231
_symmetry_Int_Tables_number   1
_cell_volume   316.435
_cell_formula_units_Z   2
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
  Ba  Ba0  1  0.741  0.741  0.746  1.0
  Ba  Ba1  1  0.259  0.259  0.254  1.0
  Tb  Tb2  1  0.906  0.539  0.727  1.0
  Tb  Tb3  1  0.094  0.461  0.273  1.0
  Tb  Tb4  1  0.461  0.094  0.273  1.0
  Tb  Tb5  1  0.539  0.906  0.727  1.0
  Mn  Mn6  1  0.141  0.349  0.755  1.0
  Mn  Mn7  1  0.651  0.859  0.245  1.0
  Mn  Mn8  1  0.859  0.651  0.245  1.0
  Mn  Mn9  1  0.349  0.141  0.755  1.0
  O  O10  1  0.118  0.882  0.500  1.0
  O  O11  1  0.400  0.600  0.500  1.0
  O  O12  1  0.535  0.114  0.716  1.0
  O  O13  1  0.465  0.886  0.284  1.0
  O  O14  1  0.128  0.872  0.000  1.0
  O  O15  1  0.872  0.128  0.000  1.0
  O  O16  1  0.600  0.400  0.500  1.0
  O  O17  1  0.886  0.465  0.284  1.0
  O  O18  1  0.220  0.220  0.764  1.0
  O  O19  1  0.114  0.535  0.716  1.0
  O  O20  1  0.391  0.609  0.000  1.0
  O  O21  1  0.609  0.391  0.000  1.0
  O  O22  1  0.780  0.780  0.236  1.0
  O  O23  1  0.882  0.118  0.500  1.0
[/CIF]
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The crystal structure described by BaTb2Mn2O7 crystallizes in the monoclinic C2/m space group. Ba(1) is bonded in a 12-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(4), two equivalent O(6), and four equivalent O(5) atoms. Tb(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), one O(6), and three equivalent O(3) atoms. Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 5-27°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms to form distorted OBa2Tb2Mn2 octahedra that share corners with two equivalent O(6)Ba2Tb2Mn2 octahedra, corners with four equivalent O(5)Ba4Mn2 octahedra,  an edgeedge with one O(2)Ba2Tb2Mn2 octahedra, faces with two equivalent O(6)Ba2Tb2Mn2 octahedra, and faces with two equivalent O(5)Ba4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. In the third O site, O(3) is bonded in a 4-coordinate geometry to three equivalent Tb(1) and one Mn(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms. In the fifth O site, O(5) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form distorted OBa4Mn2 octahedra that share corners with four equivalent O(2)Ba2Tb2Mn2 octahedra, corners with four equivalent O(6)Ba2Tb2Mn2 octahedra, corners with four equivalent O(5)Ba4Mn2 octahedra, edges with four equivalent O(5)Ba4Mn2 octahedra, faces with two equivalent O(2)Ba2Tb2Mn2 octahedra, and faces with two equivalent O(6)Ba2Tb2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 4-63°. In the sixth O site, O(6) is bonded to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Mn(1) atoms to form distorted OBa2Tb2Mn2 octahedra that share corners with two equivalent O(2)Ba2Tb2Mn2 octahedra, corners with four equivalent O(5)Ba4Mn2 octahedra,  an edgeedge with one O(6)Ba2Tb2Mn2 octahedra, faces with two equivalent O(2)Ba2Tb2Mn2 octahedra, and faces with two equivalent O(5)Ba4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 57-63°. is represented by the CIF file [CIF]
data_BaTb2Mn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.357
_cell_length_b   10.357
_cell_length_c   5.603
_cell_angle_alpha   89.998
_cell_angle_beta   89.998
_cell_angle_gamma   148.231
_symmetry_Int_Tables_number   1
_cell_volume   316.435
_cell_formula_units_Z   2
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
  Ba  Ba0  1  0.741  0.741  0.746  1.0
  Ba  Ba1  1  0.259  0.259  0.254  1.0
  Tb  Tb2  1  0.906  0.539  0.727  1.0
  Tb  Tb3  1  0.094  0.461  0.273  1.0
  Tb  Tb4  1  0.461  0.094  0.273  1.0
  Tb  Tb5  1  0.539  0.906  0.727  1.0
  Mn  Mn6  1  0.141  0.349  0.755  1.0
  Mn  Mn7  1  0.651  0.859  0.245  1.0
  Mn  Mn8  1  0.859  0.651  0.245  1.0
  Mn  Mn9  1  0.349  0.141  0.755  1.0
  O  O10  1  0.118  0.882  0.500  1.0
  O  O11  1  0.400  0.600  0.500  1.0
  O  O12  1  0.535  0.114  0.716  1.0
  O  O13  1  0.465  0.886  0.284  1.0
  O  O14  1  0.128  0.872  0.000  1.0
  O  O15  1  0.872  0.128  0.000  1.0
  O  O16  1  0.600  0.400  0.500  1.0
  O  O17  1  0.886  0.465  0.284  1.0
  O  O18  1  0.220  0.220  0.764  1.0
  O  O19  1  0.114  0.535  0.716  1.0
  O  O20  1  0.391  0.609  0.000  1.0
  O  O21  1  0.609  0.391  0.000  1.0
  O  O22  1  0.780  0.780  0.236  1.0
  O  O23  1  0.882  0.118  0.500  1.0
[/CIF]
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