The structure described by Sr2MgHfCrO6 crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), and two equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and two equivalent O(1) atoms. Mg(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 MgO6 octahedra that share faces with two equivalent Hf(1)O6 octahedra. Hf(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 HfO6 octahedra that share faces with two equivalent Mg(1)O6 octahedra. Cr(1) is bonded in a square co-planar geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Mg(1), and one Hf(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(2), two equivalent Sr(1), one Mg(1), and one Hf(1) atom. In the third O site, O(3) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. In the fifth O site, O(5) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. In the sixth O site, O(6) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. is represented by the CIF file [CIF]
data_Sr2HfMgCrO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.840
_cell_length_b   6.841
_cell_length_c   6.334
_cell_angle_alpha   72.214
_cell_angle_beta   131.816
_cell_angle_gamma   131.356
_symmetry_Int_Tables_number   1
_cell_volume   160.908
_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
  Sr  Sr0  1  0.555  0.232  0.772  1.0
  Sr  Sr1  1  0.499  0.802  0.295  1.0
  Hf  Hf2  1  0.022  0.512  0.532  1.0
  Mg  Mg3  1  0.521  0.512  0.033  1.0
  Cr  Cr4  1  0.024  0.014  0.033  1.0
  O  O5  1  0.200  0.348  0.564  1.0
  O  O6  1  0.824  0.657  0.500  1.0
  O  O7  1  0.496  0.189  0.176  1.0
  O  O8  1  0.548  0.835  0.883  1.0
  O  O9  1  0.987  0.683  0.175  1.0
  O  O10  1  0.060  0.346  0.894  1.0
[/CIF]
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The structure described by Sr2MgHfCrO6 crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), and two equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and two equivalent O(1) atoms. Mg(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 MgO6 octahedra that share faces with two equivalent Hf(1)O6 octahedra. Hf(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 HfO6 octahedra that share faces with two equivalent Mg(1)O6 octahedra. Cr(1) is bonded in a square co-planar geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Mg(1), and one Hf(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(2), two equivalent Sr(1), one Mg(1), and one Hf(1) atom. In the third O site, O(3) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. In the fifth O site, O(5) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. In the sixth O site, O(6) is bonded to one Sr(1), one Sr(2), one Mg(1), one Hf(1), and one Cr(1) atom to form a mixture of distorted face, corner, and edge-sharing OSr2HfMgCr trigonal bipyramids. is represented by the CIF file [CIF]
data_Sr2HfMgCrO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.840
_cell_length_b   6.841
_cell_length_c   6.334
_cell_angle_alpha   72.214
_cell_angle_beta   131.816
_cell_angle_gamma   131.356
_symmetry_Int_Tables_number   1
_cell_volume   160.908
_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
  Sr  Sr0  1  0.555  0.232  0.772  1.0
  Sr  Sr1  1  0.499  0.802  0.295  1.0
  Hf  Hf2  1  0.022  0.512  0.532  1.0
  Mg  Mg3  1  0.521  0.512  0.033  1.0
  Cr  Cr4  1  0.024  0.014  0.033  1.0
  O  O5  1  0.200  0.348  0.564  1.0
  O  O6  1  0.824  0.657  0.500  1.0
  O  O7  1  0.496  0.189  0.176  1.0
  O  O8  1  0.548  0.835  0.883  1.0
  O  O9  1  0.987  0.683  0.175  1.0
  O  O10  1  0.060  0.346  0.894  1.0
[/CIF]
.