The crystal structure described by SrMg14HfO16 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. Sr(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form SrO6 octahedra that share corners with two equivalent Sr(1)O6 octahedra; corners with four equivalent Mg(1)O6 octahedra; edges with four equivalent Mg(4)O6 octahedra; and edges with eight Mg(2,2)O6 octahedra. The corner-sharing octahedra are not tilted. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form MgO6 octahedra that share corners with two equivalent Sr(1)O6 octahedra; corners with two equivalent Mg(1)O6 octahedra; corners with two equivalent Hf(1)O6 octahedra; edges with four Mg(2,2)O6 octahedra; edges with four equivalent Mg(3)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedra are not tilted. In the second Mg site, Mg(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(3)O6 octahedra; corners with four Mg(2,2)O6 octahedra; edges with two equivalent Sr(1)O6 octahedra; edges with two equivalent Mg(1)O6 octahedra; edges with two Mg(2,2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the third Mg site, Mg(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(3)O6 octahedra; corners with four Mg(2,2)O6 octahedra; edges with two equivalent Sr(1)O6 octahedra; edges with two equivalent Mg(1)O6 octahedra; edges with two Mg(2,2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the fourth Mg site, Mg(3) is bonded to one O(5), one O(6), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra; corners with four equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(1)O6 octahedra; edges with two Mg(2,2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; edges with two equivalent Hf(1)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth Mg site, Mg(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Mg(4)O6 octahedra,  an edgeedge with one Sr(1)O6 octahedra,  an edgeedge with one Hf(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Mg(2)O6 octahedra, and edges with four equivalent Mg(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. Hf(1) is bonded to two equivalent O(6) and four equivalent O(2) atoms to form HfO6 octahedra that share corners with two equivalent Hf(1)O6 octahedra, corners with four equivalent Mg(1)O6 octahedra, edges with four equivalent Mg(4)O6 octahedra, and edges with eight equivalent Mg(3)O6 octahedra. The corner-sharing octahedra are not tilted. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Mg(1), two equivalent Mg(2), and two equivalent Mg(4) atoms to form OSrMg5 octahedra that share corners with two equivalent O(2)HfMg5 octahedra, corners with four equivalent O(1)SrMg5 octahedra, edges with two equivalent O(2)HfMg5 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with two equivalent O(4)Sr2Mg4 octahedra, edges with two equivalent O(1)SrMg5 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the second O site, O(2) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), and one Hf(1) atom to form OHfMg5 octahedra that share corners with two equivalent O(1)SrMg5 octahedra, corners with four equivalent O(2)HfMg5 octahedra, edges with two equivalent O(6)Hf2Mg4 octahedra, edges with two equivalent O(2)HfMg5 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with two equivalent O(1)SrMg5 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third O site, O(3) is bonded to two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form OMg6 octahedra that share corners with six equivalent O(3)Mg6 octahedra,  an edgeedge with one O(6)Hf2Mg4 octahedra,  an edgeedge with one O(4)Sr2Mg4 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with four equivalent O(2)HfMg5 octahedra, and edges with four equivalent O(1)SrMg5 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the fourth O site, O(4) is bonded to two equivalent Sr(1) and four Mg(2,2) atoms to form OSr2Mg4 octahedra that share corners with two equivalent O(4)Sr2Mg4 octahedra, corners with four equivalent O(5)Mg6 octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with eight equivalent O(1)SrMg5 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded to two equivalent Mg(1); two Mg(2,2); and two equivalent Mg(3) atoms to form OMg6 octahedra that share corners with two equivalent O(6)Hf2Mg4 octahedra, corners with two equivalent O(5)Mg6 octahedra, corners with two equivalent O(4)Sr2Mg4 octahedra, edges with four equivalent O(2)HfMg5 octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with four equivalent O(1)SrMg5 octahedra. The corner-sharing octahedra are not tilted. In the sixth O site, O(6) is bonded to four equivalent Mg(3) and two equivalent Hf(1) atoms to form OHf2Mg4 octahedra that share corners with two equivalent O(6)Hf2Mg4 octahedra, corners with four equivalent O(5)Mg6 octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with eight equivalent O(2)HfMg5 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrHfMg14O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.772
_cell_length_b   8.772
_cell_length_c   4.452
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   342.588
_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  0.000  0.000  0.000  1.0
  Hf  Hf1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.000  0.500  0.000  1.0
  Mg  Mg3  1  0.500  0.000  0.000  1.0
  Mg  Mg4  1  0.000  0.258  0.500  1.0
  Mg  Mg5  1  0.000  0.742  0.500  1.0
  Mg  Mg6  1  0.500  0.245  0.500  1.0
  Mg  Mg7  1  0.500  0.755  0.500  1.0
  Mg  Mg8  1  0.258  0.000  0.500  1.0
  Mg  Mg9  1  0.245  0.500  0.500  1.0
  Mg  Mg10  1  0.742  0.000  0.500  1.0
  Mg  Mg11  1  0.755  0.500  0.500  1.0
  Mg  Mg12  1  0.250  0.250  0.000  1.0
  Mg  Mg13  1  0.250  0.750  0.000  1.0
  Mg  Mg14  1  0.750  0.250  0.000  1.0
  Mg  Mg15  1  0.750  0.750  0.000  1.0
  O  O16  1  0.271  0.000  0.000  1.0
  O  O17  1  0.250  0.500  0.000  1.0
  O  O18  1  0.729  0.000  0.000  1.0
  O  O19  1  0.750  0.500  0.000  1.0
  O  O20  1  0.250  0.250  0.500  1.0
  O  O21  1  0.250  0.750  0.500  1.0
  O  O22  1  0.750  0.250  0.500  1.0
  O  O23  1  0.750  0.750  0.500  1.0
  O  O24  1  0.000  0.000  0.500  1.0
  O  O25  1  0.000  0.500  0.500  1.0
  O  O26  1  0.500  0.000  0.500  1.0
  O  O27  1  0.500  0.500  0.500  1.0
  O  O28  1  0.000  0.271  0.000  1.0
  O  O29  1  0.000  0.729  0.000  1.0
  O  O30  1  0.500  0.250  0.000  1.0
  O  O31  1  0.500  0.750  0.000  1.0
[/CIF]
.
The crystal structure described by SrMg14HfO16 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. Sr(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form SrO6 octahedra that share corners with two equivalent Sr(1)O6 octahedra; corners with four equivalent Mg(1)O6 octahedra; edges with four equivalent Mg(4)O6 octahedra; and edges with eight Mg(2,2)O6 octahedra. The corner-sharing octahedra are not tilted. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form MgO6 octahedra that share corners with two equivalent Sr(1)O6 octahedra; corners with two equivalent Mg(1)O6 octahedra; corners with two equivalent Hf(1)O6 octahedra; edges with four Mg(2,2)O6 octahedra; edges with four equivalent Mg(3)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedra are not tilted. In the second Mg site, Mg(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(3)O6 octahedra; corners with four Mg(2,2)O6 octahedra; edges with two equivalent Sr(1)O6 octahedra; edges with two equivalent Mg(1)O6 octahedra; edges with two Mg(2,2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the third Mg site, Mg(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(3)O6 octahedra; corners with four Mg(2,2)O6 octahedra; edges with two equivalent Sr(1)O6 octahedra; edges with two equivalent Mg(1)O6 octahedra; edges with two Mg(2,2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the fourth Mg site, Mg(3) is bonded to one O(5), one O(6), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra; corners with four equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(1)O6 octahedra; edges with two Mg(2,2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; edges with two equivalent Hf(1)O6 octahedra; and edges with four equivalent Mg(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth Mg site, Mg(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Mg(4)O6 octahedra,  an edgeedge with one Sr(1)O6 octahedra,  an edgeedge with one Hf(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Mg(2)O6 octahedra, and edges with four equivalent Mg(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. Hf(1) is bonded to two equivalent O(6) and four equivalent O(2) atoms to form HfO6 octahedra that share corners with two equivalent Hf(1)O6 octahedra, corners with four equivalent Mg(1)O6 octahedra, edges with four equivalent Mg(4)O6 octahedra, and edges with eight equivalent Mg(3)O6 octahedra. The corner-sharing octahedra are not tilted. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Mg(1), two equivalent Mg(2), and two equivalent Mg(4) atoms to form OSrMg5 octahedra that share corners with two equivalent O(2)HfMg5 octahedra, corners with four equivalent O(1)SrMg5 octahedra, edges with two equivalent O(2)HfMg5 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with two equivalent O(4)Sr2Mg4 octahedra, edges with two equivalent O(1)SrMg5 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the second O site, O(2) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), and one Hf(1) atom to form OHfMg5 octahedra that share corners with two equivalent O(1)SrMg5 octahedra, corners with four equivalent O(2)HfMg5 octahedra, edges with two equivalent O(6)Hf2Mg4 octahedra, edges with two equivalent O(2)HfMg5 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with two equivalent O(1)SrMg5 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third O site, O(3) is bonded to two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form OMg6 octahedra that share corners with six equivalent O(3)Mg6 octahedra,  an edgeedge with one O(6)Hf2Mg4 octahedra,  an edgeedge with one O(4)Sr2Mg4 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with four equivalent O(2)HfMg5 octahedra, and edges with four equivalent O(1)SrMg5 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the fourth O site, O(4) is bonded to two equivalent Sr(1) and four Mg(2,2) atoms to form OSr2Mg4 octahedra that share corners with two equivalent O(4)Sr2Mg4 octahedra, corners with four equivalent O(5)Mg6 octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with eight equivalent O(1)SrMg5 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded to two equivalent Mg(1); two Mg(2,2); and two equivalent Mg(3) atoms to form OMg6 octahedra that share corners with two equivalent O(6)Hf2Mg4 octahedra, corners with two equivalent O(5)Mg6 octahedra, corners with two equivalent O(4)Sr2Mg4 octahedra, edges with four equivalent O(2)HfMg5 octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with four equivalent O(1)SrMg5 octahedra. The corner-sharing octahedra are not tilted. In the sixth O site, O(6) is bonded to four equivalent Mg(3) and two equivalent Hf(1) atoms to form OHf2Mg4 octahedra that share corners with two equivalent O(6)Hf2Mg4 octahedra, corners with four equivalent O(5)Mg6 octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with eight equivalent O(2)HfMg5 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrHfMg14O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.772
_cell_length_b   8.772
_cell_length_c   4.452
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   342.588
_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  0.000  0.000  0.000  1.0
  Hf  Hf1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.000  0.500  0.000  1.0
  Mg  Mg3  1  0.500  0.000  0.000  1.0
  Mg  Mg4  1  0.000  0.258  0.500  1.0
  Mg  Mg5  1  0.000  0.742  0.500  1.0
  Mg  Mg6  1  0.500  0.245  0.500  1.0
  Mg  Mg7  1  0.500  0.755  0.500  1.0
  Mg  Mg8  1  0.258  0.000  0.500  1.0
  Mg  Mg9  1  0.245  0.500  0.500  1.0
  Mg  Mg10  1  0.742  0.000  0.500  1.0
  Mg  Mg11  1  0.755  0.500  0.500  1.0
  Mg  Mg12  1  0.250  0.250  0.000  1.0
  Mg  Mg13  1  0.250  0.750  0.000  1.0
  Mg  Mg14  1  0.750  0.250  0.000  1.0
  Mg  Mg15  1  0.750  0.750  0.000  1.0
  O  O16  1  0.271  0.000  0.000  1.0
  O  O17  1  0.250  0.500  0.000  1.0
  O  O18  1  0.729  0.000  0.000  1.0
  O  O19  1  0.750  0.500  0.000  1.0
  O  O20  1  0.250  0.250  0.500  1.0
  O  O21  1  0.250  0.750  0.500  1.0
  O  O22  1  0.750  0.250  0.500  1.0
  O  O23  1  0.750  0.750  0.500  1.0
  O  O24  1  0.000  0.000  0.500  1.0
  O  O25  1  0.000  0.500  0.500  1.0
  O  O26  1  0.500  0.000  0.500  1.0
  O  O27  1  0.500  0.500  0.500  1.0
  O  O28  1  0.000  0.271  0.000  1.0
  O  O29  1  0.000  0.729  0.000  1.0
  O  O30  1  0.500  0.250  0.000  1.0
  O  O31  1  0.500  0.750  0.000  1.0
[/CIF]
.