The material structure described by BaCe2O4 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form a mixture of corner and edge-sharing CeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-64°. In the second Ce site, Ce(2) is bonded to one O(3), two equivalent O(1), and three equivalent O(4) atoms to form a mixture of corner and edge-sharing CeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-64°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Ce(1), and two equivalent Ce(2) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1) and three equivalent Ce(1) atoms to form a mixture of corner and edge-sharing OBa2Ce3 square pyramids. In the third O site, O(3) is bonded to two equivalent Ba(1), one Ce(2), and two equivalent Ce(1) atoms to form a mixture of distorted corner and edge-sharing OBa2Ce3 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ba(1) and three equivalent Ce(2) atoms to form a mixture of distorted corner and edge-sharing OBa2Ce3 trigonal bipyramids. is represented by the CIF file [CIF]
data_BaCe2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.644
_cell_length_b   10.656
_cell_length_c   12.563
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   487.816
_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
  Ba  Ba0  1  0.250  0.250  0.352  1.0
  Ba  Ba1  1  0.250  0.750  0.148  1.0
  Ba  Ba2  1  0.750  0.750  0.648  1.0
  Ba  Ba3  1  0.750  0.250  0.852  1.0
  Ce  Ce4  1  0.250  0.076  0.612  1.0
  Ce  Ce5  1  0.250  0.576  0.888  1.0
  Ce  Ce6  1  0.750  0.924  0.388  1.0
  Ce  Ce7  1  0.750  0.424  0.112  1.0
  Ce  Ce8  1  0.250  0.580  0.388  1.0
  Ce  Ce9  1  0.250  0.080  0.112  1.0
  Ce  Ce10  1  0.750  0.420  0.612  1.0
  Ce  Ce11  1  0.750  0.920  0.888  1.0
  O  O12  1  0.250  0.287  0.674  1.0
  O  O13  1  0.250  0.787  0.826  1.0
  O  O14  1  0.750  0.713  0.326  1.0
  O  O15  1  0.750  0.213  0.174  1.0
  O  O16  1  0.250  0.378  0.983  1.0
  O  O17  1  0.250  0.878  0.517  1.0
  O  O18  1  0.750  0.622  0.017  1.0
  O  O19  1  0.750  0.122  0.483  1.0
  O  O20  1  0.250  0.486  0.216  1.0
  O  O21  1  0.250  0.986  0.284  1.0
  O  O22  1  0.750  0.514  0.784  1.0
  O  O23  1  0.750  0.014  0.716  1.0
  O  O24  1  0.250  0.069  0.924  1.0
  O  O25  1  0.250  0.569  0.576  1.0
  O  O26  1  0.750  0.931  0.076  1.0
  O  O27  1  0.750  0.431  0.424  1.0
[/CIF]
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The material structure described by BaCe2O4 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form a mixture of corner and edge-sharing CeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-64°. In the second Ce site, Ce(2) is bonded to one O(3), two equivalent O(1), and three equivalent O(4) atoms to form a mixture of corner and edge-sharing CeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-64°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Ce(1), and two equivalent Ce(2) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1) and three equivalent Ce(1) atoms to form a mixture of corner and edge-sharing OBa2Ce3 square pyramids. In the third O site, O(3) is bonded to two equivalent Ba(1), one Ce(2), and two equivalent Ce(1) atoms to form a mixture of distorted corner and edge-sharing OBa2Ce3 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ba(1) and three equivalent Ce(2) atoms to form a mixture of distorted corner and edge-sharing OBa2Ce3 trigonal bipyramids. is represented by the CIF file [CIF]
data_BaCe2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.644
_cell_length_b   10.656
_cell_length_c   12.563
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   487.816
_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
  Ba  Ba0  1  0.250  0.250  0.352  1.0
  Ba  Ba1  1  0.250  0.750  0.148  1.0
  Ba  Ba2  1  0.750  0.750  0.648  1.0
  Ba  Ba3  1  0.750  0.250  0.852  1.0
  Ce  Ce4  1  0.250  0.076  0.612  1.0
  Ce  Ce5  1  0.250  0.576  0.888  1.0
  Ce  Ce6  1  0.750  0.924  0.388  1.0
  Ce  Ce7  1  0.750  0.424  0.112  1.0
  Ce  Ce8  1  0.250  0.580  0.388  1.0
  Ce  Ce9  1  0.250  0.080  0.112  1.0
  Ce  Ce10  1  0.750  0.420  0.612  1.0
  Ce  Ce11  1  0.750  0.920  0.888  1.0
  O  O12  1  0.250  0.287  0.674  1.0
  O  O13  1  0.250  0.787  0.826  1.0
  O  O14  1  0.750  0.713  0.326  1.0
  O  O15  1  0.750  0.213  0.174  1.0
  O  O16  1  0.250  0.378  0.983  1.0
  O  O17  1  0.250  0.878  0.517  1.0
  O  O18  1  0.750  0.622  0.017  1.0
  O  O19  1  0.750  0.122  0.483  1.0
  O  O20  1  0.250  0.486  0.216  1.0
  O  O21  1  0.250  0.986  0.284  1.0
  O  O22  1  0.750  0.514  0.784  1.0
  O  O23  1  0.750  0.014  0.716  1.0
  O  O24  1  0.250  0.069  0.924  1.0
  O  O25  1  0.250  0.569  0.576  1.0
  O  O26  1  0.750  0.931  0.076  1.0
  O  O27  1  0.750  0.431  0.424  1.0
[/CIF]
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