The material described by MgNi9O13 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(3), two equivalent O(7), and two equivalent O(9) atoms. There are nine inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(10), one O(11), two equivalent O(12), and two equivalent O(13) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-6°. In the second Ni site, Ni(2) is bonded to one O(5), one O(6), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 5-11°. In the third Ni site, Ni(3) is bonded to one O(4), one O(7), two equivalent O(1), and two equivalent O(5) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 5-13°. In the fourth Ni site, Ni(4) is bonded to one O(13), one O(8), two equivalent O(10), and two equivalent O(12) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-10°. In the fifth Ni site, Ni(5) is bonded to one O(12), one O(9), two equivalent O(11), and two equivalent O(13) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-11°. In the sixth Ni site, Ni(6) is bonded to one O(1), one O(2), two equivalent O(4), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-55°. In the seventh Ni site, Ni(7) is bonded to one O(1), one O(3), two equivalent O(5), and two equivalent O(7) atoms to form a mixture of distorted edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-63°. In the eighth Ni site, Ni(8) is bonded to one O(12), one O(2), two equivalent O(10), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-55°. In the ninth Ni site, Ni(9) is bonded to one O(13), one O(3), two equivalent O(11), and two equivalent O(9) atoms to form a mixture of distorted edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-63°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded to one Ni(6), one Ni(7), two equivalent Ni(2), and two equivalent Ni(3) atoms to form ONi6 octahedra that share corners with two equivalent O(4)Ni5 square pyramids, corners with two equivalent O(5)Ni5 square pyramids,  a cornercorner with one O(3)Mg2Ni2 tetrahedra, edges with two equivalent O(1)Ni6 octahedra, edges with three equivalent O(4)Ni5 square pyramids, edges with three equivalent O(5)Ni5 square pyramids, and edges with two equivalent O(7)Mg2Ni3 trigonal bipyramids. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(6) and one Ni(8) atom. In the third O site, O(3) is bonded to two equivalent Mg(1), one Ni(7), and one Ni(9) atom to form OMg2Ni2 tetrahedra that share  a cornercorner with one O(1)Ni6 octahedra,  a cornercorner with one O(13)Ni6 octahedra, corners with two equivalent O(11)Ni5 square pyramids, corners with two equivalent O(5)Ni5 square pyramids, corners with two equivalent O(3)Mg2Ni2 tetrahedra, corners with four equivalent O(7)Mg2Ni3 trigonal bipyramids, corners with four equivalent O(9)Mg2Ni3 trigonal bipyramids,  an edgeedge with one O(7)Mg2Ni3 trigonal bipyramid, and  an edgeedge with one O(9)Mg2Ni3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 6°. In the fourth O site, O(4) is bonded to one Ni(3), two equivalent Ni(2), and two equivalent Ni(6) atoms to form ONi5 square pyramids that share corners with two equivalent O(1)Ni6 octahedra,  a cornercorner with one O(7)Mg2Ni3 trigonal bipyramid, edges with three equivalent O(1)Ni6 octahedra, edges with two equivalent O(4)Ni5 square pyramids, and edges with two equivalent O(5)Ni5 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the fifth O site, O(5) is bonded to one Ni(2), two equivalent Ni(3), and two equivalent Ni(7) atoms to form ONi5 square pyramids that share corners with two equivalent O(1)Ni6 octahedra, corners with two equivalent O(3)Mg2Ni2 tetrahedra, corners with four equivalent O(7)Mg2Ni3 trigonal bipyramids, edges with three equivalent O(1)Ni6 octahedra, edges with two equivalent O(4)Ni5 square pyramids, edges with two equivalent O(5)Ni5 square pyramids, and  an edgeedge with one O(7)Mg2Ni3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 9°. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(2) and two equivalent Ni(6) atoms. In the seventh O site, O(7) is bonded to two equivalent Mg(1), one Ni(3), and two equivalent Ni(7) atoms to form distorted OMg2Ni3 trigonal bipyramids that share  a cornercorner with one O(4)Ni5 square pyramid, corners with four equivalent O(5)Ni5 square pyramids, corners with four equivalent O(3)Mg2Ni2 tetrahedra, corners with two equivalent O(9)Mg2Ni3 trigonal bipyramids, edges with two equivalent O(1)Ni6 octahedra,  an edgeedge with one O(5)Ni5 square pyramid,  an edgeedge with one O(3)Mg2Ni2 tetrahedra,  an edgeedge with one O(9)Mg2Ni3 trigonal bipyramid, and edges with two equivalent O(7)Mg2Ni3 trigonal bipyramids. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Ni(4) and two equivalent Ni(8) atoms. In the ninth O site, O(9) is bonded to two equivalent Mg(1), one Ni(5), and two equivalent Ni(9) atoms to form distorted OMg2Ni3 trigonal bipyramids that share  a cornercorner with one O(12)Ni6 octahedra, corners with four equivalent O(11)Ni5 square pyramids, corners with four equivalent O(3)Mg2Ni2 tetrahedra, corners with two equivalent O(7)Mg2Ni3 trigonal bipyramids, edges with two equivalent O(13)Ni6 octahedra,  an edgeedge with one O(11)Ni5 square pyramid,  an edgeedge with one O(3)Mg2Ni2 tetrahedra,  an edgeedge with one O(7)Mg2Ni3 trigonal bipyramid, and edges with two equivalent O(9)Mg2Ni3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. In the tenth O site, O(10) is bonded to one Ni(1), two equivalent Ni(4), and two equivalent Ni(8) atoms to form ONi5 square pyramids that share corners with two equivalent O(12)Ni6 octahedra,  a cornercorner with one O(11)Ni5 square pyramid, edges with two equivalent O(13)Ni6 octahedra, edges with three equivalent O(12)Ni6 octahedra, and edges with two equivalent O(10)Ni5 square pyramids. The corner-sharing octahedral tilt angles are 6°. In the eleventh O site, O(11) is bonded to one Ni(1), two equivalent Ni(5), and two equivalent Ni(9) atoms to form ONi5 square pyramids that share corners with two equivalent O(13)Ni6 octahedra,  a cornercorner with one O(10)Ni5 square pyramid, corners with two equivalent O(3)Mg2Ni2 tetrahedra, corners with four equivalent O(9)Mg2Ni3 trigonal bipyramids, edges with two equivalent O(12)Ni6 octahedra, edges with three equivalent O(13)Ni6 octahedra, edges with two equivalent O(11)Ni5 square pyramids, and  an edgeedge with one O(9)Mg2Ni3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 7°. In the twelfth O site, O(12) is bonded to one Ni(5), one Ni(8), two equivalent Ni(1), and two equivalent Ni(4) atoms to form ONi6 octahedra that share corners with two equivalent O(13)Ni6 octahedra, corners with two equivalent O(10)Ni5 square pyramids,  a cornercorner with one O(9)Mg2Ni3 trigonal bipyramid, edges with two equivalent O(12)Ni6 octahedra, edges with three equivalent O(13)Ni6 octahedra, edges with two equivalent O(11)Ni5 square pyramids, and edges with three equivalent O(10)Ni5 square pyramids. The corner-sharing octahedral tilt angles are 4°. In the thirteenth O site, O(13) is bonded to one Ni(4), one Ni(9), two equivalent Ni(1), and two equivalent Ni(5) atoms to form ONi6 octahedra that share corners with two equivalent O(12)Ni6 octahedra, corners with two equivalent O(11)Ni5 square pyramids,  a cornercorner with one O(3)Mg2Ni2 tetrahedra, edges with two equivalent O(13)Ni6 octahedra, edges with three equivalent O(12)Ni6 octahedra, edges with two equivalent O(10)Ni5 square pyramids, edges with three equivalent O(11)Ni5 square pyramids, and edges with two equivalent O(9)Mg2Ni3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. is represented by the CIF file [CIF]
data_MgNi9O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.907
_cell_length_b   5.113
_cell_length_c   16.044
_cell_angle_alpha   99.043
_cell_angle_beta   89.986
_cell_angle_gamma   106.518
_symmetry_Int_Tables_number   1
_cell_volume   225.547
_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
  Mg  Mg0  1  0.788  0.577  0.770  1.0
  Ni  Ni1  1  0.499  0.999  0.498  1.0
  Ni  Ni2  1  0.650  0.300  0.048  1.0
  Ni  Ni3  1  0.353  0.706  0.962  1.0
  Ni  Ni4  1  0.750  0.499  0.412  1.0
  Ni  Ni5  1  0.250  0.500  0.580  1.0
  Ni  Ni6  1  0.941  0.881  0.125  1.0
  Ni  Ni7  1  0.065  0.130  0.877  1.0
  Ni  Ni8  1  0.996  0.992  0.334  1.0
  Ni  Ni9  1  0.007  0.015  0.667  1.0
  O  O10  1  1.000  0.999  0.010  1.0
  O  O11  1  0.881  0.760  0.228  1.0
  O  O12  1  0.140  0.279  0.772  1.0
  O  O13  1  0.301  0.603  0.076  1.0
  O  O14  1  0.705  0.410  0.933  1.0
  O  O15  1  0.569  0.137  0.152  1.0
  O  O16  1  0.418  0.835  0.854  1.0
  O  O17  1  0.610  0.223  0.309  1.0
  O  O18  1  0.373  0.748  0.689  1.0
  O  O19  1  0.385  0.769  0.383  1.0
  O  O20  1  0.619  0.240  0.611  1.0
  O  O21  1  0.124  0.249  0.454  1.0
  O  O22  1  0.868  0.737  0.532  1.0
[/CIF]
.
The material described by MgNi9O13 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(3), two equivalent O(7), and two equivalent O(9) atoms. There are nine inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(10), one O(11), two equivalent O(12), and two equivalent O(13) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-6°. In the second Ni site, Ni(2) is bonded to one O(5), one O(6), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 5-11°. In the third Ni site, Ni(3) is bonded to one O(4), one O(7), two equivalent O(1), and two equivalent O(5) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 5-13°. In the fourth Ni site, Ni(4) is bonded to one O(13), one O(8), two equivalent O(10), and two equivalent O(12) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-10°. In the fifth Ni site, Ni(5) is bonded to one O(12), one O(9), two equivalent O(11), and two equivalent O(13) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-11°. In the sixth Ni site, Ni(6) is bonded to one O(1), one O(2), two equivalent O(4), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-55°. In the seventh Ni site, Ni(7) is bonded to one O(1), one O(3), two equivalent O(5), and two equivalent O(7) atoms to form a mixture of distorted edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-63°. In the eighth Ni site, Ni(8) is bonded to one O(12), one O(2), two equivalent O(10), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-55°. In the ninth Ni site, Ni(9) is bonded to one O(13), one O(3), two equivalent O(11), and two equivalent O(9) atoms to form a mixture of distorted edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 1-63°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded to one Ni(6), one Ni(7), two equivalent Ni(2), and two equivalent Ni(3) atoms to form ONi6 octahedra that share corners with two equivalent O(4)Ni5 square pyramids, corners with two equivalent O(5)Ni5 square pyramids,  a cornercorner with one O(3)Mg2Ni2 tetrahedra, edges with two equivalent O(1)Ni6 octahedra, edges with three equivalent O(4)Ni5 square pyramids, edges with three equivalent O(5)Ni5 square pyramids, and edges with two equivalent O(7)Mg2Ni3 trigonal bipyramids. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(6) and one Ni(8) atom. In the third O site, O(3) is bonded to two equivalent Mg(1), one Ni(7), and one Ni(9) atom to form OMg2Ni2 tetrahedra that share  a cornercorner with one O(1)Ni6 octahedra,  a cornercorner with one O(13)Ni6 octahedra, corners with two equivalent O(11)Ni5 square pyramids, corners with two equivalent O(5)Ni5 square pyramids, corners with two equivalent O(3)Mg2Ni2 tetrahedra, corners with four equivalent O(7)Mg2Ni3 trigonal bipyramids, corners with four equivalent O(9)Mg2Ni3 trigonal bipyramids,  an edgeedge with one O(7)Mg2Ni3 trigonal bipyramid, and  an edgeedge with one O(9)Mg2Ni3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 6°. In the fourth O site, O(4) is bonded to one Ni(3), two equivalent Ni(2), and two equivalent Ni(6) atoms to form ONi5 square pyramids that share corners with two equivalent O(1)Ni6 octahedra,  a cornercorner with one O(7)Mg2Ni3 trigonal bipyramid, edges with three equivalent O(1)Ni6 octahedra, edges with two equivalent O(4)Ni5 square pyramids, and edges with two equivalent O(5)Ni5 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the fifth O site, O(5) is bonded to one Ni(2), two equivalent Ni(3), and two equivalent Ni(7) atoms to form ONi5 square pyramids that share corners with two equivalent O(1)Ni6 octahedra, corners with two equivalent O(3)Mg2Ni2 tetrahedra, corners with four equivalent O(7)Mg2Ni3 trigonal bipyramids, edges with three equivalent O(1)Ni6 octahedra, edges with two equivalent O(4)Ni5 square pyramids, edges with two equivalent O(5)Ni5 square pyramids, and  an edgeedge with one O(7)Mg2Ni3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 9°. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(2) and two equivalent Ni(6) atoms. In the seventh O site, O(7) is bonded to two equivalent Mg(1), one Ni(3), and two equivalent Ni(7) atoms to form distorted OMg2Ni3 trigonal bipyramids that share  a cornercorner with one O(4)Ni5 square pyramid, corners with four equivalent O(5)Ni5 square pyramids, corners with four equivalent O(3)Mg2Ni2 tetrahedra, corners with two equivalent O(9)Mg2Ni3 trigonal bipyramids, edges with two equivalent O(1)Ni6 octahedra,  an edgeedge with one O(5)Ni5 square pyramid,  an edgeedge with one O(3)Mg2Ni2 tetrahedra,  an edgeedge with one O(9)Mg2Ni3 trigonal bipyramid, and edges with two equivalent O(7)Mg2Ni3 trigonal bipyramids. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Ni(4) and two equivalent Ni(8) atoms. In the ninth O site, O(9) is bonded to two equivalent Mg(1), one Ni(5), and two equivalent Ni(9) atoms to form distorted OMg2Ni3 trigonal bipyramids that share  a cornercorner with one O(12)Ni6 octahedra, corners with four equivalent O(11)Ni5 square pyramids, corners with four equivalent O(3)Mg2Ni2 tetrahedra, corners with two equivalent O(7)Mg2Ni3 trigonal bipyramids, edges with two equivalent O(13)Ni6 octahedra,  an edgeedge with one O(11)Ni5 square pyramid,  an edgeedge with one O(3)Mg2Ni2 tetrahedra,  an edgeedge with one O(7)Mg2Ni3 trigonal bipyramid, and edges with two equivalent O(9)Mg2Ni3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. In the tenth O site, O(10) is bonded to one Ni(1), two equivalent Ni(4), and two equivalent Ni(8) atoms to form ONi5 square pyramids that share corners with two equivalent O(12)Ni6 octahedra,  a cornercorner with one O(11)Ni5 square pyramid, edges with two equivalent O(13)Ni6 octahedra, edges with three equivalent O(12)Ni6 octahedra, and edges with two equivalent O(10)Ni5 square pyramids. The corner-sharing octahedral tilt angles are 6°. In the eleventh O site, O(11) is bonded to one Ni(1), two equivalent Ni(5), and two equivalent Ni(9) atoms to form ONi5 square pyramids that share corners with two equivalent O(13)Ni6 octahedra,  a cornercorner with one O(10)Ni5 square pyramid, corners with two equivalent O(3)Mg2Ni2 tetrahedra, corners with four equivalent O(9)Mg2Ni3 trigonal bipyramids, edges with two equivalent O(12)Ni6 octahedra, edges with three equivalent O(13)Ni6 octahedra, edges with two equivalent O(11)Ni5 square pyramids, and  an edgeedge with one O(9)Mg2Ni3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 7°. In the twelfth O site, O(12) is bonded to one Ni(5), one Ni(8), two equivalent Ni(1), and two equivalent Ni(4) atoms to form ONi6 octahedra that share corners with two equivalent O(13)Ni6 octahedra, corners with two equivalent O(10)Ni5 square pyramids,  a cornercorner with one O(9)Mg2Ni3 trigonal bipyramid, edges with two equivalent O(12)Ni6 octahedra, edges with three equivalent O(13)Ni6 octahedra, edges with two equivalent O(11)Ni5 square pyramids, and edges with three equivalent O(10)Ni5 square pyramids. The corner-sharing octahedral tilt angles are 4°. In the thirteenth O site, O(13) is bonded to one Ni(4), one Ni(9), two equivalent Ni(1), and two equivalent Ni(5) atoms to form ONi6 octahedra that share corners with two equivalent O(12)Ni6 octahedra, corners with two equivalent O(11)Ni5 square pyramids,  a cornercorner with one O(3)Mg2Ni2 tetrahedra, edges with two equivalent O(13)Ni6 octahedra, edges with three equivalent O(12)Ni6 octahedra, edges with two equivalent O(10)Ni5 square pyramids, edges with three equivalent O(11)Ni5 square pyramids, and edges with two equivalent O(9)Mg2Ni3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. is represented by the CIF file [CIF]
data_MgNi9O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.907
_cell_length_b   5.113
_cell_length_c   16.044
_cell_angle_alpha   99.043
_cell_angle_beta   89.986
_cell_angle_gamma   106.518
_symmetry_Int_Tables_number   1
_cell_volume   225.547
_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
  Mg  Mg0  1  0.788  0.577  0.770  1.0
  Ni  Ni1  1  0.499  0.999  0.498  1.0
  Ni  Ni2  1  0.650  0.300  0.048  1.0
  Ni  Ni3  1  0.353  0.706  0.962  1.0
  Ni  Ni4  1  0.750  0.499  0.412  1.0
  Ni  Ni5  1  0.250  0.500  0.580  1.0
  Ni  Ni6  1  0.941  0.881  0.125  1.0
  Ni  Ni7  1  0.065  0.130  0.877  1.0
  Ni  Ni8  1  0.996  0.992  0.334  1.0
  Ni  Ni9  1  0.007  0.015  0.667  1.0
  O  O10  1  1.000  0.999  0.010  1.0
  O  O11  1  0.881  0.760  0.228  1.0
  O  O12  1  0.140  0.279  0.772  1.0
  O  O13  1  0.301  0.603  0.076  1.0
  O  O14  1  0.705  0.410  0.933  1.0
  O  O15  1  0.569  0.137  0.152  1.0
  O  O16  1  0.418  0.835  0.854  1.0
  O  O17  1  0.610  0.223  0.309  1.0
  O  O18  1  0.373  0.748  0.689  1.0
  O  O19  1  0.385  0.769  0.383  1.0
  O  O20  1  0.619  0.240  0.611  1.0
  O  O21  1  0.124  0.249  0.454  1.0
  O  O22  1  0.868  0.737  0.532  1.0
[/CIF]
.