The material described by BaCa2I6 is Molybdenite-derived structured and crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form BaI6 octahedra that share corners with four equivalent Ca(1)I6 pentagonal pyramids and edges with four equivalent Ca(1)I6 pentagonal pyramids. Ca(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form distorted CaI6 pentagonal pyramids that share corners with two equivalent Ba(1)I6 octahedra, corners with two equivalent Ca(1)I6 pentagonal pyramids, edges with two equivalent Ba(1)I6 octahedra, and edges with two equivalent Ca(1)I6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 46-75°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. In the third I site, I(3) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCa2I6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.071
_cell_length_b   7.485
_cell_length_c   15.655
_cell_angle_alpha   66.039
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   864.260
_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  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.500  0.000  0.500  1.0
  Ca  Ca2  1  0.604  0.662  0.253  1.0
  Ca  Ca3  1  0.104  0.338  0.247  1.0
  Ca  Ca4  1  0.896  0.662  0.753  1.0
  Ca  Ca5  1  0.396  0.338  0.747  1.0
  I  I6  1  0.328  0.683  0.105  1.0
  I  I7  1  0.812  0.552  0.105  1.0
  I  I8  1  0.400  0.038  0.276  1.0
  I  I9  1  0.900  0.962  0.224  1.0
  I  I10  1  0.312  0.448  0.395  1.0
  I  I11  1  0.828  0.317  0.395  1.0
  I  I12  1  0.172  0.683  0.605  1.0
  I  I13  1  0.688  0.552  0.605  1.0
  I  I14  1  0.100  0.038  0.776  1.0
  I  I15  1  0.600  0.962  0.724  1.0
  I  I16  1  0.188  0.448  0.895  1.0
  I  I17  1  0.672  0.317  0.895  1.0
[/CIF]
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The material described by BaCa2I6 is Molybdenite-derived structured and crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form BaI6 octahedra that share corners with four equivalent Ca(1)I6 pentagonal pyramids and edges with four equivalent Ca(1)I6 pentagonal pyramids. Ca(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form distorted CaI6 pentagonal pyramids that share corners with two equivalent Ba(1)I6 octahedra, corners with two equivalent Ca(1)I6 pentagonal pyramids, edges with two equivalent Ba(1)I6 octahedra, and edges with two equivalent Ca(1)I6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 46-75°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. In the third I site, I(3) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCa2I6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.071
_cell_length_b   7.485
_cell_length_c   15.655
_cell_angle_alpha   66.039
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   864.260
_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  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.500  0.000  0.500  1.0
  Ca  Ca2  1  0.604  0.662  0.253  1.0
  Ca  Ca3  1  0.104  0.338  0.247  1.0
  Ca  Ca4  1  0.896  0.662  0.753  1.0
  Ca  Ca5  1  0.396  0.338  0.747  1.0
  I  I6  1  0.328  0.683  0.105  1.0
  I  I7  1  0.812  0.552  0.105  1.0
  I  I8  1  0.400  0.038  0.276  1.0
  I  I9  1  0.900  0.962  0.224  1.0
  I  I10  1  0.312  0.448  0.395  1.0
  I  I11  1  0.828  0.317  0.395  1.0
  I  I12  1  0.172  0.683  0.605  1.0
  I  I13  1  0.688  0.552  0.605  1.0
  I  I14  1  0.100  0.038  0.776  1.0
  I  I15  1  0.600  0.962  0.724  1.0
  I  I16  1  0.188  0.448  0.895  1.0
  I  I17  1  0.672  0.317  0.895  1.0
[/CIF]
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