The material described by Ba2MgNb6(NO7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(10), one O(13), two equivalent O(1), two equivalent O(3), two equivalent O(6), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded to two equivalent O(12), two equivalent O(14), and two equivalent O(9) atoms to form distorted BaO6 pentagonal pyramids that share corners with two equivalent Nb(4)NO5 octahedra, corners with two equivalent Nb(6)NO5 octahedra, and faces with two equivalent Ba(2)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 58-69°. Mg(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(7), and two equivalent O(5) atoms. 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 to one O(2), one O(3), one O(6), one O(7), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share  a cornercorner with one Nb(4)NO5 octahedra,  a cornercorner with one Nb(6)NO5 octahedra, and corners with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-31°. In the third Nb site, Nb(3) is bonded in a 5-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  a cornercorner with one Nb(2)O6 octahedra, corners with two equivalent Nb(4)NO5 octahedra, corners with two equivalent Ba(2)O6 pentagonal pyramids,  an edgeedge with one Nb(6)NO5 octahedra, and edges with two equivalent Nb(5)N3O3 octahedra. The corner-sharing octahedral tilt angles range from 3-20°. In the fifth Nb site, Nb(5) is bonded to one N(2), two equivalent N(1), one O(10), one O(11), and one O(13) atom to form distorted NbN3O3 octahedra that share corners with two equivalent Nb(5)N3O3 octahedra, edges with two equivalent Nb(4)NO5 octahedra, and edges with two equivalent Nb(6)NO5 octahedra. The corner-sharing octahedral tilt angles are 36°. 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  a cornercorner with one Nb(2)O6 octahedra, corners with two equivalent Nb(6)NO5 octahedra, corners with two equivalent Ba(2)O6 pentagonal pyramids,  an edgeedge with one Nb(4)NO5 octahedra, and edges with two equivalent Nb(5)N3O3 octahedra. The corner-sharing octahedral tilt angles range from 0-20°. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Nb(4), one Nb(6), and two equivalent Nb(5) atoms to form NNb4 trigonal pyramids that share corners with two equivalent N(1)Nb4 trigonal pyramids and  an edgeedge with one O(12)Ba2Nb2 tetrahedra. In the second N site, N(2) is bonded in a linear geometry to 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 a mixture of distorted edge and corner-sharing OMgNb3 trigonal pyramids. In the third O site, O(3) is bonded in a linear geometry to two equivalent Ba(1), one Nb(2), and one Nb(6) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Nb(1), one Nb(3), and two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to two equivalent Mg(1), one Nb(1), and one Nb(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Ba(1), one Nb(2), and one Nb(4) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Nb(2), and two equivalent Nb(3) atoms to form a mixture of edge and corner-sharing OMgNb3 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar 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 4-coordinate geometry to one Ba(1), one Nb(5), and two equivalent Nb(4) atoms. In the eleventh O site, O(11) is bonded in a bent 150 degrees 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 distorted OBa2Nb2 tetrahedra that share corners with two equivalent O(12)Ba2Nb2 tetrahedra and  an edgeedge with one N(1)Nb4 trigonal pyramid. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ba(1), one Nb(5), and two equivalent Nb(6) atoms. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to two equivalent Ba(2) and one Nb(1) atom. is represented by the CIF file [CIF]
data_Ba2MgNb6(NO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.274
_cell_length_b   10.905
_cell_length_c   3.969
_cell_angle_alpha   79.416
_cell_angle_beta   90.011
_cell_angle_gamma   89.157
_symmetry_Int_Tables_number   1
_cell_volume   394.461
_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  0.251  0.771  0.111  1.0
  Ba  Ba1  1  0.782  0.043  0.977  1.0
  Mg  Mg2  1  0.251  0.164  0.918  1.0
  Nb  Nb3  1  0.035  0.298  0.350  1.0
  Nb  Nb4  1  0.261  0.477  0.759  1.0
  Nb  Nb5  1  0.465  0.275  0.362  1.0
  Nb  Nb6  1  0.581  0.754  0.620  1.0
  Nb  Nb7  1  0.735  0.538  0.229  1.0
  Nb  Nb8  1  0.933  0.715  0.640  1.0
  N  N9  1  0.732  0.598  0.699  1.0
  N  N10  1  0.887  0.414  0.291  1.0
  O  O11  1  0.053  0.853  0.569  1.0
  O  O12  1  0.101  0.301  0.848  1.0
  O  O13  1  0.097  0.595  0.700  1.0
  O  O14  1  0.236  0.431  0.283  1.0
  O  O15  1  0.272  0.165  0.417  1.0
  O  O16  1  0.395  0.600  0.697  1.0
  O  O17  1  0.407  0.298  0.850  1.0
  O  O18  1  0.415  0.858  0.566  1.0
  O  O19  1  0.605  0.154  0.422  1.0
  O  O20  1  0.571  0.722  0.136  1.0
  O  O21  1  0.573  0.429  0.284  1.0
  O  O22  1  0.743  0.862  0.566  1.0
  O  O23  1  0.903  0.697  0.149  1.0
  O  O24  1  0.941  0.146  0.426  1.0
[/CIF]
.
The material described by Ba2MgNb6(NO7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(10), one O(13), two equivalent O(1), two equivalent O(3), two equivalent O(6), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded to two equivalent O(12), two equivalent O(14), and two equivalent O(9) atoms to form distorted BaO6 pentagonal pyramids that share corners with two equivalent Nb(4)NO5 octahedra, corners with two equivalent Nb(6)NO5 octahedra, and faces with two equivalent Ba(2)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 58-69°. Mg(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(7), and two equivalent O(5) atoms. 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 to one O(2), one O(3), one O(6), one O(7), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share  a cornercorner with one Nb(4)NO5 octahedra,  a cornercorner with one Nb(6)NO5 octahedra, and corners with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-31°. In the third Nb site, Nb(3) is bonded in a 5-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  a cornercorner with one Nb(2)O6 octahedra, corners with two equivalent Nb(4)NO5 octahedra, corners with two equivalent Ba(2)O6 pentagonal pyramids,  an edgeedge with one Nb(6)NO5 octahedra, and edges with two equivalent Nb(5)N3O3 octahedra. The corner-sharing octahedral tilt angles range from 3-20°. In the fifth Nb site, Nb(5) is bonded to one N(2), two equivalent N(1), one O(10), one O(11), and one O(13) atom to form distorted NbN3O3 octahedra that share corners with two equivalent Nb(5)N3O3 octahedra, edges with two equivalent Nb(4)NO5 octahedra, and edges with two equivalent Nb(6)NO5 octahedra. The corner-sharing octahedral tilt angles are 36°. 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  a cornercorner with one Nb(2)O6 octahedra, corners with two equivalent Nb(6)NO5 octahedra, corners with two equivalent Ba(2)O6 pentagonal pyramids,  an edgeedge with one Nb(4)NO5 octahedra, and edges with two equivalent Nb(5)N3O3 octahedra. The corner-sharing octahedral tilt angles range from 0-20°. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Nb(4), one Nb(6), and two equivalent Nb(5) atoms to form NNb4 trigonal pyramids that share corners with two equivalent N(1)Nb4 trigonal pyramids and  an edgeedge with one O(12)Ba2Nb2 tetrahedra. In the second N site, N(2) is bonded in a linear geometry to 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 a mixture of distorted edge and corner-sharing OMgNb3 trigonal pyramids. In the third O site, O(3) is bonded in a linear geometry to two equivalent Ba(1), one Nb(2), and one Nb(6) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Nb(1), one Nb(3), and two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to two equivalent Mg(1), one Nb(1), and one Nb(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Ba(1), one Nb(2), and one Nb(4) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Nb(2), and two equivalent Nb(3) atoms to form a mixture of edge and corner-sharing OMgNb3 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar 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 4-coordinate geometry to one Ba(1), one Nb(5), and two equivalent Nb(4) atoms. In the eleventh O site, O(11) is bonded in a bent 150 degrees 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 distorted OBa2Nb2 tetrahedra that share corners with two equivalent O(12)Ba2Nb2 tetrahedra and  an edgeedge with one N(1)Nb4 trigonal pyramid. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ba(1), one Nb(5), and two equivalent Nb(6) atoms. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to two equivalent Ba(2) and one Nb(1) atom. is represented by the CIF file [CIF]
data_Ba2MgNb6(NO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.274
_cell_length_b   10.905
_cell_length_c   3.969
_cell_angle_alpha   79.416
_cell_angle_beta   90.011
_cell_angle_gamma   89.157
_symmetry_Int_Tables_number   1
_cell_volume   394.461
_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  0.251  0.771  0.111  1.0
  Ba  Ba1  1  0.782  0.043  0.977  1.0
  Mg  Mg2  1  0.251  0.164  0.918  1.0
  Nb  Nb3  1  0.035  0.298  0.350  1.0
  Nb  Nb4  1  0.261  0.477  0.759  1.0
  Nb  Nb5  1  0.465  0.275  0.362  1.0
  Nb  Nb6  1  0.581  0.754  0.620  1.0
  Nb  Nb7  1  0.735  0.538  0.229  1.0
  Nb  Nb8  1  0.933  0.715  0.640  1.0
  N  N9  1  0.732  0.598  0.699  1.0
  N  N10  1  0.887  0.414  0.291  1.0
  O  O11  1  0.053  0.853  0.569  1.0
  O  O12  1  0.101  0.301  0.848  1.0
  O  O13  1  0.097  0.595  0.700  1.0
  O  O14  1  0.236  0.431  0.283  1.0
  O  O15  1  0.272  0.165  0.417  1.0
  O  O16  1  0.395  0.600  0.697  1.0
  O  O17  1  0.407  0.298  0.850  1.0
  O  O18  1  0.415  0.858  0.566  1.0
  O  O19  1  0.605  0.154  0.422  1.0
  O  O20  1  0.571  0.722  0.136  1.0
  O  O21  1  0.573  0.429  0.284  1.0
  O  O22  1  0.743  0.862  0.566  1.0
  O  O23  1  0.903  0.697  0.149  1.0
  O  O24  1  0.941  0.146  0.426  1.0
[/CIF]
.