The structure described by MgNb4(CoO6)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one O(7), and one O(9) atom to form distorted MgO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(3)O6 octahedra,  a cornercorner with one Co(1)O4 tetrahedra,  a cornercorner with one Co(2)O4 tetrahedra, and  an edgeedge with one Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-49°. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(10), one O(11), one O(2), one O(3), one O(4), and one O(9) atom to form distorted NbO6 octahedra that share  a cornercorner with one Co(2)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Co(1)O4 tetrahedra,  an edgeedge with one Nb(2)O6 octahedra, and  an edgeedge with one Nb(3)O6 octahedra. In the second Nb site, Nb(2) is bonded to one O(12), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Nb(1)O6 octahedra,  an edgeedge with one Nb(3)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. In the third Nb site, Nb(3) is bonded to one O(1), one O(10), one O(11), one O(5), one O(6), and one O(7) atom to form distorted NbO6 octahedra that share  a cornercorner with one Co(1)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Nb(1)O6 octahedra, and  an edgeedge with one Nb(2)O6 octahedra. In the fourth Nb site, Nb(4) is bonded in a 5-coordinate geometry to one O(11), one O(12), one O(4), one O(5), and one O(8) atom. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(5), one O(8), and one O(9) atom to form distorted CoO4 tetrahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, and  a cornercorner with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-53°. In the second Co site, Co(2) is bonded to one O(1), one O(12), one O(4), and one O(6) atom to form distorted CoO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Nb(3)O6 octahedra, and  a cornercorner with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(3), and one Co(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Co(1) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(4), and one Co(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Nb(3), one Nb(4), and one Co(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Nb(2), one Nb(3), and one Co(2) atom. In the seventh O site, O(7) is bonded in a T-shaped geometry to one Mg(1), one Nb(2), and one Nb(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Nb(2), one Nb(4), and one Co(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Mg(1), one Nb(1), and one Co(1) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Nb(1) and one Nb(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(3), and one Nb(4) atom. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Nb(2), one Nb(4), and one Co(2) atom. is represented by the CIF file [CIF]
data_MgNb4(CoO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.333
_cell_length_b   6.018
_cell_length_c   5.992
_cell_angle_alpha   85.065
_cell_angle_beta   60.722
_cell_angle_gamma   60.877
_symmetry_Int_Tables_number   1
_cell_volume   251.298
_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  0.325  0.320  0.706  1.0
  Nb  Nb1  1  0.023  0.991  0.970  1.0
  Nb  Nb2  1  0.339  0.937  0.041  1.0
  Nb  Nb3  1  0.643  0.029  0.017  1.0
  Nb  Nb4  1  0.846  0.567  0.428  1.0
  Co  Co5  1  0.109  0.594  0.456  1.0
  Co  Co6  1  0.549  0.545  0.397  1.0
  O  O7  1  0.493  0.284  0.333  1.0
  O  O8  1  0.164  0.798  0.171  1.0
  O  O9  1  0.190  0.126  0.818  1.0
  O  O10  1  0.825  0.301  0.287  1.0
  O  O11  1  0.838  0.700  0.728  1.0
  O  O12  1  0.497  0.823  0.205  1.0
  O  O13  1  0.480  0.176  0.875  1.0
  O  O14  1  0.126  0.294  0.284  1.0
  O  O15  1  0.174  0.685  0.704  1.0
  O  O16  1  0.828  0.141  0.866  1.0
  O  O17  1  0.836  0.802  0.202  1.0
  O  O18  1  0.549  0.701  0.689  1.0
[/CIF]
.
The structure described by MgNb4(CoO6)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one O(7), and one O(9) atom to form distorted MgO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(3)O6 octahedra,  a cornercorner with one Co(1)O4 tetrahedra,  a cornercorner with one Co(2)O4 tetrahedra, and  an edgeedge with one Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-49°. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(10), one O(11), one O(2), one O(3), one O(4), and one O(9) atom to form distorted NbO6 octahedra that share  a cornercorner with one Co(2)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Co(1)O4 tetrahedra,  an edgeedge with one Nb(2)O6 octahedra, and  an edgeedge with one Nb(3)O6 octahedra. In the second Nb site, Nb(2) is bonded to one O(12), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Co(1)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Nb(1)O6 octahedra,  an edgeedge with one Nb(3)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. In the third Nb site, Nb(3) is bonded to one O(1), one O(10), one O(11), one O(5), one O(6), and one O(7) atom to form distorted NbO6 octahedra that share  a cornercorner with one Co(1)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Nb(1)O6 octahedra, and  an edgeedge with one Nb(2)O6 octahedra. In the fourth Nb site, Nb(4) is bonded in a 5-coordinate geometry to one O(11), one O(12), one O(4), one O(5), and one O(8) atom. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(5), one O(8), and one O(9) atom to form distorted CoO4 tetrahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, and  a cornercorner with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-53°. In the second Co site, Co(2) is bonded to one O(1), one O(12), one O(4), and one O(6) atom to form distorted CoO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Nb(3)O6 octahedra, and  a cornercorner with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(3), and one Co(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Co(1) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(4), and one Co(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Nb(3), one Nb(4), and one Co(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Nb(2), one Nb(3), and one Co(2) atom. In the seventh O site, O(7) is bonded in a T-shaped geometry to one Mg(1), one Nb(2), and one Nb(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Nb(2), one Nb(4), and one Co(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Mg(1), one Nb(1), and one Co(1) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Nb(1) and one Nb(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(3), and one Nb(4) atom. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Nb(2), one Nb(4), and one Co(2) atom. is represented by the CIF file [CIF]
data_MgNb4(CoO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.333
_cell_length_b   6.018
_cell_length_c   5.992
_cell_angle_alpha   85.065
_cell_angle_beta   60.722
_cell_angle_gamma   60.877
_symmetry_Int_Tables_number   1
_cell_volume   251.298
_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  0.325  0.320  0.706  1.0
  Nb  Nb1  1  0.023  0.991  0.970  1.0
  Nb  Nb2  1  0.339  0.937  0.041  1.0
  Nb  Nb3  1  0.643  0.029  0.017  1.0
  Nb  Nb4  1  0.846  0.567  0.428  1.0
  Co  Co5  1  0.109  0.594  0.456  1.0
  Co  Co6  1  0.549  0.545  0.397  1.0
  O  O7  1  0.493  0.284  0.333  1.0
  O  O8  1  0.164  0.798  0.171  1.0
  O  O9  1  0.190  0.126  0.818  1.0
  O  O10  1  0.825  0.301  0.287  1.0
  O  O11  1  0.838  0.700  0.728  1.0
  O  O12  1  0.497  0.823  0.205  1.0
  O  O13  1  0.480  0.176  0.875  1.0
  O  O14  1  0.126  0.294  0.284  1.0
  O  O15  1  0.174  0.685  0.704  1.0
  O  O16  1  0.828  0.141  0.866  1.0
  O  O17  1  0.836  0.802  0.202  1.0
  O  O18  1  0.549  0.701  0.689  1.0
[/CIF]
.