The compound described by Be2Tb2O5 crystallizes in the tetragonal P4/mmm space group. Be(1) is bonded to one O(2) and four equivalent O(1) atoms to form distorted BeO5 square pyramids that share corners with five equivalent Be(1)O5 square pyramids and faces with four equivalent Tb(2)O12 cuboctahedra. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Tb site, Tb(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form TbO12 cuboctahedra that share corners with four equivalent Tb(2)O12 cuboctahedra, faces with four equivalent Tb(2)O12 cuboctahedra, and faces with eight equivalent Be(1)O5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Be(1), two equivalent Tb(1), and two equivalent Tb(2) atoms. In the second O site, O(2) is bonded in a linear geometry to two equivalent Be(1) and four equivalent Tb(2) atoms. is represented by the CIF card [CIF]
data_Tb2Be2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.615
_cell_length_b   3.615
_cell_length_c   6.799
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   88.880
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Tb  Tb1  1  0.000  0.000  0.500  1.0
  Be  Be2  1  0.500  0.500  0.268  1.0
  Be  Be3  1  0.500  0.500  0.732  1.0
  O  O4  1  0.500  0.000  0.222  1.0
  O  O5  1  0.500  0.000  0.778  1.0
  O  O6  1  0.000  0.500  0.222  1.0
  O  O7  1  0.000  0.500  0.778  1.0
  O  O8  1  0.500  0.500  0.500  1.0
[/CIF]
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The compound described by Be2Tb2O5 crystallizes in the tetragonal P4/mmm space group. Be(1) is bonded to one O(2) and four equivalent O(1) atoms to form distorted BeO5 square pyramids that share corners with five equivalent Be(1)O5 square pyramids and faces with four equivalent Tb(2)O12 cuboctahedra. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Tb site, Tb(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form TbO12 cuboctahedra that share corners with four equivalent Tb(2)O12 cuboctahedra, faces with four equivalent Tb(2)O12 cuboctahedra, and faces with eight equivalent Be(1)O5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Be(1), two equivalent Tb(1), and two equivalent Tb(2) atoms. In the second O site, O(2) is bonded in a linear geometry to two equivalent Be(1) and four equivalent Tb(2) atoms. is represented by the CIF card [CIF]
data_Tb2Be2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.615
_cell_length_b   3.615
_cell_length_c   6.799
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   88.880
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Tb  Tb1  1  0.000  0.000  0.500  1.0
  Be  Be2  1  0.500  0.500  0.268  1.0
  Be  Be3  1  0.500  0.500  0.732  1.0
  O  O4  1  0.500  0.000  0.222  1.0
  O  O5  1  0.500  0.000  0.778  1.0
  O  O6  1  0.000  0.500  0.222  1.0
  O  O7  1  0.000  0.500  0.778  1.0
  O  O8  1  0.500  0.500  0.500  1.0
[/CIF]
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