The compound described by SrMg6Hf crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form SrMg12 cuboctahedra that share corners with four equivalent Sr(1)Mg12 cuboctahedra, corners with eight equivalent Hf(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with four equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, and faces with four equivalent Hf(1)Mg12 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Sr(1), two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(2), and two equivalent Hf(1) atoms to form distorted MgSr2Hf2Mg8 cuboctahedra that share corners with twelve equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, edges with four equivalent Sr(1)Mg12 cuboctahedra, edges with four equivalent Hf(1)Mg12 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with two equivalent Hf(1)Mg12 cuboctahedra, and faces with six equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Sr(1), two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and two equivalent Hf(1) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to two equivalent Sr(1), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Sr(1), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms. Hf(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form HfMg12 cuboctahedra that share corners with four equivalent Hf(1)Mg12 cuboctahedra, corners with eight equivalent Sr(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, faces with two equivalent Hf(1)Mg12 cuboctahedra, faces with four equivalent Sr(1)Mg12 cuboctahedra, and faces with four equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra. is represented by the CIF card [CIF]
data_SrHfMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.750
_cell_length_b   6.555
_cell_length_c   6.555
_cell_angle_alpha   93.677
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   203.663
_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
  Hf  Hf0  1  0.000  0.376  0.624  1.0
  Mg  Mg1  1  1.000  0.371  0.127  1.0
  Mg  Mg2  1  0.000  0.873  0.629  1.0
  Mg  Mg3  1  0.500  0.150  0.395  1.0
  Mg  Mg4  1  0.500  0.605  0.850  1.0
  Mg  Mg5  1  0.500  0.608  0.392  1.0
  Mg  Mg6  1  0.500  0.145  0.855  1.0
  Sr  Sr7  1  0.000  0.872  0.128  1.0
[/CIF]
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The compound described by SrMg6Hf crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form SrMg12 cuboctahedra that share corners with four equivalent Sr(1)Mg12 cuboctahedra, corners with eight equivalent Hf(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with four equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, and faces with four equivalent Hf(1)Mg12 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Sr(1), two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(2), and two equivalent Hf(1) atoms to form distorted MgSr2Hf2Mg8 cuboctahedra that share corners with twelve equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, edges with four equivalent Sr(1)Mg12 cuboctahedra, edges with four equivalent Hf(1)Mg12 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with two equivalent Hf(1)Mg12 cuboctahedra, and faces with six equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Sr(1), two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and two equivalent Hf(1) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to two equivalent Sr(1), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Sr(1), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms. Hf(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form HfMg12 cuboctahedra that share corners with four equivalent Hf(1)Mg12 cuboctahedra, corners with eight equivalent Sr(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra, faces with two equivalent Hf(1)Mg12 cuboctahedra, faces with four equivalent Sr(1)Mg12 cuboctahedra, and faces with four equivalent Mg(1)Sr2Hf2Mg8 cuboctahedra. is represented by the CIF card [CIF]
data_SrHfMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.750
_cell_length_b   6.555
_cell_length_c   6.555
_cell_angle_alpha   93.677
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   203.663
_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
  Hf  Hf0  1  0.000  0.376  0.624  1.0
  Mg  Mg1  1  1.000  0.371  0.127  1.0
  Mg  Mg2  1  0.000  0.873  0.629  1.0
  Mg  Mg3  1  0.500  0.150  0.395  1.0
  Mg  Mg4  1  0.500  0.605  0.850  1.0
  Mg  Mg5  1  0.500  0.608  0.392  1.0
  Mg  Mg6  1  0.500  0.145  0.855  1.0
  Sr  Sr7  1  0.000  0.872  0.128  1.0
[/CIF]
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