The compound described by Mg9CuO10 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. In the second Mg site, Mg(2) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(4)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra,  an edgeedge with one Cu(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with three equivalent Mg(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the third Mg site, Mg(3) is bonded to one O(1), two equivalent O(5), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth Mg site, Mg(4) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mg(5)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with three equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the fifth Mg site, Mg(5) is bonded to one O(2), two equivalent O(5), and three equivalent O(4) atoms to form MgO6 octahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with three equivalent Mg(4)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, edges with three equivalent Mg(4)O6 octahedra, and edges with four equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. Cu(1) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form CuO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra, corners with four equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, edges with four equivalent Mg(4)O6 octahedra, and edges with four equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(2), one Mg(3), two equivalent Mg(1), and two equivalent Mg(4) atoms to form OMg6 octahedra that share  a cornercorner with one O(3)Mg6 octahedra,  a cornercorner with one O(5)Mg6 octahedra, corners with two equivalent O(4)Mg5Cu octahedra, corners with two equivalent O(1)Mg6 octahedra,  an edgeedge with one O(4)Mg5Cu octahedra, edges with two equivalent O(2)Mg4Cu2 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with three equivalent O(1)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second O site, O(2) is bonded to one Mg(4), one Mg(5), two equivalent Mg(2), and two equivalent Cu(1) atoms to form OMg4Cu2 octahedra that share  a cornercorner with one O(4)Mg5Cu octahedra,  a cornercorner with one O(5)Mg6 octahedra, corners with two equivalent O(2)Mg4Cu2 octahedra, corners with two equivalent O(3)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(1)Mg6 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with three equivalent O(2)Mg4Cu2 octahedra, and edges with four equivalent O(4)Mg5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the third O site, O(3) is bonded to one Mg(1), two equivalent Mg(2), and three equivalent Mg(3) atoms to form OMg6 octahedra that share  a cornercorner with one O(1)Mg6 octahedra,  a cornercorner with one O(3)Mg6 octahedra, corners with two equivalent O(2)Mg4Cu2 octahedra, corners with two equivalent O(5)Mg6 octahedra,  an edgeedge with one O(2)Mg4Cu2 octahedra, edges with three equivalent O(5)Mg6 octahedra, edges with four equivalent O(1)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth O site, O(4) is bonded to two equivalent Mg(4), three equivalent Mg(5), and one Cu(1) atom to form OMg5Cu octahedra that share  a cornercorner with one O(2)Mg4Cu2 octahedra,  a cornercorner with one O(4)Mg5Cu octahedra, corners with two equivalent O(1)Mg6 octahedra, corners with two equivalent O(5)Mg6 octahedra,  an edgeedge with one O(1)Mg6 octahedra, edges with three equivalent O(5)Mg6 octahedra, edges with four equivalent O(2)Mg4Cu2 octahedra, and edges with four equivalent O(4)Mg5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth O site, O(5) is bonded to one Mg(2), one Mg(4), two equivalent Mg(3), and two equivalent Mg(5) atoms to form OMg6 octahedra that share  a cornercorner with one O(2)Mg4Cu2 octahedra,  a cornercorner with one O(1)Mg6 octahedra, corners with two equivalent O(4)Mg5Cu octahedra, corners with two equivalent O(3)Mg6 octahedra, edges with two equivalent O(2)Mg4Cu2 octahedra, edges with two equivalent O(1)Mg6 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with three equivalent O(4)Mg5Cu octahedra, and edges with three equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg9CuO10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.683
_cell_length_b   6.683
_cell_length_c   10.014
_cell_angle_alpha   78.814
_cell_angle_beta   78.814
_cell_angle_gamma   26.163
_symmetry_Int_Tables_number   1
_cell_volume   193.275
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.601  0.601  0.198  1.0
  Mg  Mg2  1  0.699  0.699  0.900  1.0
  Mg  Mg3  1  0.098  0.098  0.701  1.0
  Mg  Mg4  1  0.301  0.301  0.100  1.0
  Mg  Mg5  1  0.198  0.198  0.400  1.0
  Mg  Mg6  1  0.902  0.902  0.299  1.0
  Mg  Mg7  1  0.802  0.802  0.600  1.0
  Mg  Mg8  1  0.399  0.399  0.802  1.0
  Cu  Cu9  1  0.500  0.500  0.500  1.0
  O  O10  1  0.450  0.450  0.150  1.0
  O  O11  1  0.550  0.550  0.850  1.0
  O  O12  1  0.053  0.053  0.342  1.0
  O  O13  1  0.947  0.947  0.658  1.0
  O  O14  1  0.150  0.150  0.050  1.0
  O  O15  1  0.649  0.649  0.550  1.0
  O  O16  1  0.751  0.751  0.252  1.0
  O  O17  1  0.850  0.850  0.950  1.0
  O  O18  1  0.249  0.249  0.748  1.0
  O  O19  1  0.351  0.351  0.450  1.0
[/CIF]
.
The compound described by Mg9CuO10 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. In the second Mg site, Mg(2) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(4)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra,  an edgeedge with one Cu(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with three equivalent Mg(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the third Mg site, Mg(3) is bonded to one O(1), two equivalent O(5), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth Mg site, Mg(4) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mg(5)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with three equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the fifth Mg site, Mg(5) is bonded to one O(2), two equivalent O(5), and three equivalent O(4) atoms to form MgO6 octahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with three equivalent Mg(4)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, edges with three equivalent Mg(4)O6 octahedra, and edges with four equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. Cu(1) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form CuO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra, corners with four equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, edges with four equivalent Mg(4)O6 octahedra, and edges with four equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(2), one Mg(3), two equivalent Mg(1), and two equivalent Mg(4) atoms to form OMg6 octahedra that share  a cornercorner with one O(3)Mg6 octahedra,  a cornercorner with one O(5)Mg6 octahedra, corners with two equivalent O(4)Mg5Cu octahedra, corners with two equivalent O(1)Mg6 octahedra,  an edgeedge with one O(4)Mg5Cu octahedra, edges with two equivalent O(2)Mg4Cu2 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with three equivalent O(1)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second O site, O(2) is bonded to one Mg(4), one Mg(5), two equivalent Mg(2), and two equivalent Cu(1) atoms to form OMg4Cu2 octahedra that share  a cornercorner with one O(4)Mg5Cu octahedra,  a cornercorner with one O(5)Mg6 octahedra, corners with two equivalent O(2)Mg4Cu2 octahedra, corners with two equivalent O(3)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(1)Mg6 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with three equivalent O(2)Mg4Cu2 octahedra, and edges with four equivalent O(4)Mg5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the third O site, O(3) is bonded to one Mg(1), two equivalent Mg(2), and three equivalent Mg(3) atoms to form OMg6 octahedra that share  a cornercorner with one O(1)Mg6 octahedra,  a cornercorner with one O(3)Mg6 octahedra, corners with two equivalent O(2)Mg4Cu2 octahedra, corners with two equivalent O(5)Mg6 octahedra,  an edgeedge with one O(2)Mg4Cu2 octahedra, edges with three equivalent O(5)Mg6 octahedra, edges with four equivalent O(1)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth O site, O(4) is bonded to two equivalent Mg(4), three equivalent Mg(5), and one Cu(1) atom to form OMg5Cu octahedra that share  a cornercorner with one O(2)Mg4Cu2 octahedra,  a cornercorner with one O(4)Mg5Cu octahedra, corners with two equivalent O(1)Mg6 octahedra, corners with two equivalent O(5)Mg6 octahedra,  an edgeedge with one O(1)Mg6 octahedra, edges with three equivalent O(5)Mg6 octahedra, edges with four equivalent O(2)Mg4Cu2 octahedra, and edges with four equivalent O(4)Mg5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth O site, O(5) is bonded to one Mg(2), one Mg(4), two equivalent Mg(3), and two equivalent Mg(5) atoms to form OMg6 octahedra that share  a cornercorner with one O(2)Mg4Cu2 octahedra,  a cornercorner with one O(1)Mg6 octahedra, corners with two equivalent O(4)Mg5Cu octahedra, corners with two equivalent O(3)Mg6 octahedra, edges with two equivalent O(2)Mg4Cu2 octahedra, edges with two equivalent O(1)Mg6 octahedra, edges with two equivalent O(5)Mg6 octahedra, edges with three equivalent O(4)Mg5Cu octahedra, and edges with three equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg9CuO10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.683
_cell_length_b   6.683
_cell_length_c   10.014
_cell_angle_alpha   78.814
_cell_angle_beta   78.814
_cell_angle_gamma   26.163
_symmetry_Int_Tables_number   1
_cell_volume   193.275
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.601  0.601  0.198  1.0
  Mg  Mg2  1  0.699  0.699  0.900  1.0
  Mg  Mg3  1  0.098  0.098  0.701  1.0
  Mg  Mg4  1  0.301  0.301  0.100  1.0
  Mg  Mg5  1  0.198  0.198  0.400  1.0
  Mg  Mg6  1  0.902  0.902  0.299  1.0
  Mg  Mg7  1  0.802  0.802  0.600  1.0
  Mg  Mg8  1  0.399  0.399  0.802  1.0
  Cu  Cu9  1  0.500  0.500  0.500  1.0
  O  O10  1  0.450  0.450  0.150  1.0
  O  O11  1  0.550  0.550  0.850  1.0
  O  O12  1  0.053  0.053  0.342  1.0
  O  O13  1  0.947  0.947  0.658  1.0
  O  O14  1  0.150  0.150  0.050  1.0
  O  O15  1  0.649  0.649  0.550  1.0
  O  O16  1  0.751  0.751  0.252  1.0
  O  O17  1  0.850  0.850  0.950  1.0
  O  O18  1  0.249  0.249  0.748  1.0
  O  O19  1  0.351  0.351  0.450  1.0
[/CIF]
.