The crystal structure described by Ba2MgNb6(NO7)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(5), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent O(12), two equivalent O(14), and two equivalent O(9) atoms. Mg(1) is bonded to one N(1), two equivalent N(2), one O(2), and one O(3) atom to form MgN3O2 trigonal bipyramids that share  a cornercorner with one Nb(4)NO5 octahedra, corners with two equivalent Mg(1)N3O2 trigonal bipyramids, and  an edgeedge with one Nb(6)NO5 octahedra. The corner-sharing octahedral tilt angles are 3°. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one N(2), one O(14), one O(4), one O(5), and two equivalent O(2) atoms. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(6), one O(7), and two equivalent O(4) atoms. In the third Nb site, Nb(3) is bonded in a 6-coordinate geometry to one O(11), one O(4), one O(5), one O(9), and two equivalent O(7) atoms. In the fourth Nb site, Nb(4) is bonded to one N(1), one O(12), one O(6), one O(8), and two equivalent O(10) atoms to form distorted NbNO5 octahedra that share corners with two equivalent Nb(4)NO5 octahedra,  a cornercorner with one Mg(1)N3O2 trigonal bipyramid, and  an edgeedge with one Nb(6)NO5 octahedra. The corner-sharing octahedral tilt angles are 18°. In the fifth Nb site, Nb(5) is bonded in a 6-coordinate geometry to one N(2), two equivalent N(1), one O(10), one O(11), and one O(13) atom. In the sixth Nb site, Nb(6) is bonded to one N(1), one O(1), one O(12), one O(3), and two equivalent O(13) atoms to form distorted NbNO5 octahedra that share corners with two equivalent Nb(6)NO5 octahedra,  an edgeedge with one Nb(4)NO5 octahedra, and  an edgeedge with one Mg(1)N3O2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 18°. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Mg(1), one Nb(4), one Nb(6), and two equivalent Nb(5) atoms to form NMgNb4 trigonal bipyramids that share corners with two equivalent N(1)MgNb4 trigonal bipyramids,  a cornercorner with one O(2)MgNb3 trigonal pyramid, and  an edgeedge with one O(12)Ba2Nb2 tetrahedra. In the second N site, N(2) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1), one Nb(1), and one Nb(5) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Nb(6) atom. In the second O site, O(2) is bonded to one Mg(1), one Nb(2), and two equivalent Nb(1) atoms to form distorted OMgNb3 trigonal pyramids that share corners with two equivalent O(5)Ba2Nb2 tetrahedra,  a cornercorner with one N(1)MgNb4 trigonal bipyramid, corners with two equivalent O(2)MgNb3 trigonal pyramids, and edges with two equivalent O(4)Nb4 trigonal pyramids. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one Nb(2), and one Nb(6) atom. In the fourth O site, O(4) is bonded to one Nb(1), one Nb(3), and two equivalent Nb(2) atoms to form distorted ONb4 trigonal pyramids that share corners with two equivalent O(4)Nb4 trigonal pyramids,  an edgeedge with one O(5)Ba2Nb2 tetrahedra, and edges with two equivalent O(2)MgNb3 trigonal pyramids. In the fifth O site, O(5) is bonded to two equivalent Ba(1), one Nb(1), and one Nb(3) atom to form distorted OBa2Nb2 tetrahedra that share corners with two equivalent O(5)Ba2Nb2 tetrahedra, corners with two equivalent O(2)MgNb3 trigonal pyramids, and  an edgeedge with one O(4)Nb4 trigonal pyramid. In the sixth O site, O(6) is bonded in a linear geometry to one Nb(2) and one Nb(4) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Nb(2) and two equivalent Nb(3) atoms. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Nb(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one Nb(3) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Nb(5) and two equivalent Nb(4) atoms. In the eleventh O site, O(11) is bonded in a linear geometry to one Nb(3) and one Nb(5) atom. In the twelfth O site, O(12) is bonded to two equivalent Ba(2), one Nb(4), and one Nb(6) atom to form OBa2Nb2 tetrahedra that share corners with two equivalent O(12)Ba2Nb2 tetrahedra and  an edgeedge with one N(1)MgNb4 trigonal bipyramid. In the thirteenth O site, O(13) is bonded in a 2-coordinate geometry to one Nb(5) and two equivalent Nb(6) atoms. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one Nb(1) atom. is represented by the CIF card [CIF]
data_Ba2MgNb6(NO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.111
_cell_length_b   10.655
_cell_length_c   3.985
_cell_angle_alpha   79.205
_cell_angle_beta   89.998
_cell_angle_gamma   88.662
_symmetry_Int_Tables_number   1
_cell_volume   379.928
_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
  Ba  Ba0  1  0.249  0.960  0.017  1.0
  Ba  Ba1  1  0.754  0.024  0.987  1.0
  Mg  Mg2  1  0.932  0.444  0.776  1.0
  Nb  Nb3  1  0.050  0.259  0.369  1.0
  Nb  Nb4  1  0.267  0.474  0.761  1.0
  Nb  Nb5  1  0.438  0.259  0.369  1.0
  Nb  Nb6  1  0.568  0.738  0.629  1.0
  Nb  Nb7  1  0.724  0.528  0.234  1.0
  Nb  Nb8  1  0.942  0.737  0.630  1.0
  N  N9  1  0.755  0.579  0.708  1.0
  N  N10  1  0.893  0.402  0.297  1.0
  O  O11  1  0.080  0.863  0.566  1.0
  O  O12  1  0.088  0.299  0.849  1.0
  O  O13  1  0.087  0.578  0.709  1.0
  O  O14  1  0.254  0.424  0.286  1.0
  O  O15  1  0.256  0.157  0.420  1.0
  O  O16  1  0.405  0.598  0.699  1.0
  O  O17  1  0.403  0.297  0.850  1.0
  O  O18  1  0.431  0.872  0.561  1.0
  O  O19  1  0.578  0.132  0.432  1.0
  O  O20  1  0.590  0.715  0.141  1.0
  O  O21  1  0.571  0.413  0.292  1.0
  O  O22  1  0.752  0.848  0.574  1.0
  O  O23  1  0.916  0.716  0.140  1.0
  O  O24  1  0.935  0.118  0.440  1.0
[/CIF]
.
The crystal structure described by Ba2MgNb6(NO7)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(5), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent O(12), two equivalent O(14), and two equivalent O(9) atoms. Mg(1) is bonded to one N(1), two equivalent N(2), one O(2), and one O(3) atom to form MgN3O2 trigonal bipyramids that share  a cornercorner with one Nb(4)NO5 octahedra, corners with two equivalent Mg(1)N3O2 trigonal bipyramids, and  an edgeedge with one Nb(6)NO5 octahedra. The corner-sharing octahedral tilt angles are 3°. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one N(2), one O(14), one O(4), one O(5), and two equivalent O(2) atoms. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(6), one O(7), and two equivalent O(4) atoms. In the third Nb site, Nb(3) is bonded in a 6-coordinate geometry to one O(11), one O(4), one O(5), one O(9), and two equivalent O(7) atoms. In the fourth Nb site, Nb(4) is bonded to one N(1), one O(12), one O(6), one O(8), and two equivalent O(10) atoms to form distorted NbNO5 octahedra that share corners with two equivalent Nb(4)NO5 octahedra,  a cornercorner with one Mg(1)N3O2 trigonal bipyramid, and  an edgeedge with one Nb(6)NO5 octahedra. The corner-sharing octahedral tilt angles are 18°. In the fifth Nb site, Nb(5) is bonded in a 6-coordinate geometry to one N(2), two equivalent N(1), one O(10), one O(11), and one O(13) atom. In the sixth Nb site, Nb(6) is bonded to one N(1), one O(1), one O(12), one O(3), and two equivalent O(13) atoms to form distorted NbNO5 octahedra that share corners with two equivalent Nb(6)NO5 octahedra,  an edgeedge with one Nb(4)NO5 octahedra, and  an edgeedge with one Mg(1)N3O2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 18°. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Mg(1), one Nb(4), one Nb(6), and two equivalent Nb(5) atoms to form NMgNb4 trigonal bipyramids that share corners with two equivalent N(1)MgNb4 trigonal bipyramids,  a cornercorner with one O(2)MgNb3 trigonal pyramid, and  an edgeedge with one O(12)Ba2Nb2 tetrahedra. In the second N site, N(2) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1), one Nb(1), and one Nb(5) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Nb(6) atom. In the second O site, O(2) is bonded to one Mg(1), one Nb(2), and two equivalent Nb(1) atoms to form distorted OMgNb3 trigonal pyramids that share corners with two equivalent O(5)Ba2Nb2 tetrahedra,  a cornercorner with one N(1)MgNb4 trigonal bipyramid, corners with two equivalent O(2)MgNb3 trigonal pyramids, and edges with two equivalent O(4)Nb4 trigonal pyramids. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one Nb(2), and one Nb(6) atom. In the fourth O site, O(4) is bonded to one Nb(1), one Nb(3), and two equivalent Nb(2) atoms to form distorted ONb4 trigonal pyramids that share corners with two equivalent O(4)Nb4 trigonal pyramids,  an edgeedge with one O(5)Ba2Nb2 tetrahedra, and edges with two equivalent O(2)MgNb3 trigonal pyramids. In the fifth O site, O(5) is bonded to two equivalent Ba(1), one Nb(1), and one Nb(3) atom to form distorted OBa2Nb2 tetrahedra that share corners with two equivalent O(5)Ba2Nb2 tetrahedra, corners with two equivalent O(2)MgNb3 trigonal pyramids, and  an edgeedge with one O(4)Nb4 trigonal pyramid. In the sixth O site, O(6) is bonded in a linear geometry to one Nb(2) and one Nb(4) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Nb(2) and two equivalent Nb(3) atoms. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Nb(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one Nb(3) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Nb(5) and two equivalent Nb(4) atoms. In the eleventh O site, O(11) is bonded in a linear geometry to one Nb(3) and one Nb(5) atom. In the twelfth O site, O(12) is bonded to two equivalent Ba(2), one Nb(4), and one Nb(6) atom to form OBa2Nb2 tetrahedra that share corners with two equivalent O(12)Ba2Nb2 tetrahedra and  an edgeedge with one N(1)MgNb4 trigonal bipyramid. In the thirteenth O site, O(13) is bonded in a 2-coordinate geometry to one Nb(5) and two equivalent Nb(6) atoms. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one Nb(1) atom. is represented by the CIF card [CIF]
data_Ba2MgNb6(NO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.111
_cell_length_b   10.655
_cell_length_c   3.985
_cell_angle_alpha   79.205
_cell_angle_beta   89.998
_cell_angle_gamma   88.662
_symmetry_Int_Tables_number   1
_cell_volume   379.928
_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
  Ba  Ba0  1  0.249  0.960  0.017  1.0
  Ba  Ba1  1  0.754  0.024  0.987  1.0
  Mg  Mg2  1  0.932  0.444  0.776  1.0
  Nb  Nb3  1  0.050  0.259  0.369  1.0
  Nb  Nb4  1  0.267  0.474  0.761  1.0
  Nb  Nb5  1  0.438  0.259  0.369  1.0
  Nb  Nb6  1  0.568  0.738  0.629  1.0
  Nb  Nb7  1  0.724  0.528  0.234  1.0
  Nb  Nb8  1  0.942  0.737  0.630  1.0
  N  N9  1  0.755  0.579  0.708  1.0
  N  N10  1  0.893  0.402  0.297  1.0
  O  O11  1  0.080  0.863  0.566  1.0
  O  O12  1  0.088  0.299  0.849  1.0
  O  O13  1  0.087  0.578  0.709  1.0
  O  O14  1  0.254  0.424  0.286  1.0
  O  O15  1  0.256  0.157  0.420  1.0
  O  O16  1  0.405  0.598  0.699  1.0
  O  O17  1  0.403  0.297  0.850  1.0
  O  O18  1  0.431  0.872  0.561  1.0
  O  O19  1  0.578  0.132  0.432  1.0
  O  O20  1  0.590  0.715  0.141  1.0
  O  O21  1  0.571  0.413  0.292  1.0
  O  O22  1  0.752  0.848  0.574  1.0
  O  O23  1  0.916  0.716  0.140  1.0
  O  O24  1  0.935  0.118  0.440  1.0
[/CIF]
.