The compound described by MgNb4VO12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(3), one O(4), and one O(7) atom. 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(5), and one O(8) atom to form distorted NbO6 octahedra that share corners with four equivalent Nb(4)O6 octahedra and  an edgeedge with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-46°. In the second Nb site, Nb(2) is bonded to one O(1), one O(12), one O(4), one O(6), one O(7), and one O(9) atom to form distorted NbO6 octahedra that share corners with two equivalent Nb(4)O6 octahedra and edges with two equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-40°. In the third Nb site, Nb(3) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(2), one O(4), and one O(9) atom. In the fourth Nb site, Nb(4) is bonded to one O(10), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and corners with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-63°. V(1) is bonded to one O(1), one O(11), one O(4), one O(7), one O(8), and one O(9) atom to form distorted VO6 octahedra that share corners with two equivalent Nb(4)O6 octahedra,  an edgeedge with one Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-63°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Nb(2), one Nb(3), and one V(1) atom to form distorted edge-sharing OMgNb2V trigonal pyramids. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(1), and one Nb(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Nb(2), one Nb(3), and one V(1) atom to form distorted edge-sharing OMgNb2V trigonal pyramids. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(4) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Nb(2) and one Nb(4) atom. In the seventh O site, O(7) is bonded in a distorted see-saw-like geometry to one Mg(1), one Nb(2), one Nb(4), and one V(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(4), and one V(1) atom. In the ninth O site, O(9) is bonded in a T-shaped geometry to one Nb(2), one Nb(3), and one V(1) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(4) atom. In the eleventh O site, O(11) is bonded in a distorted see-saw-like geometry to one Mg(1), one Nb(1), one Nb(3), and one V(1) atom. In the twelfth O site, O(12) is bonded in a T-shaped geometry to one Mg(1), one Nb(2), and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb4VO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.607
_cell_length_b   11.330
_cell_length_c   10.070
_cell_angle_alpha   27.531
_cell_angle_beta   50.916
_cell_angle_gamma   56.016
_symmetry_Int_Tables_number   1
_cell_volume   229.524
_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  0.795  0.507  0.769  1.0
  Nb  Nb1  1  0.018  1.000  0.990  1.0
  Nb  Nb2  1  0.971  0.495  0.015  1.0
  Nb  Nb3  1  0.469  0.998  0.516  1.0
  Nb  Nb4  1  0.520  0.502  0.487  1.0
  V  V5  1  0.296  0.996  0.290  1.0
  O  O6  1  0.366  0.306  0.104  1.0
  O  O7  1  0.233  0.101  0.636  1.0
  O  O8  1  0.093  0.312  0.745  1.0
  O  O9  1  0.855  0.199  0.213  1.0
  O  O10  1  0.337  0.803  0.134  1.0
  O  O11  1  0.733  0.396  0.338  1.0
  O  O12  1  0.212  0.628  0.603  1.0
  O  O13  1  0.596  0.190  0.864  1.0
  O  O14  1  0.127  0.818  0.706  1.0
  O  O15  1  0.842  0.698  0.235  1.0
  O  O16  1  0.711  0.865  0.366  1.0
  O  O17  1  0.636  0.681  0.835  1.0
[/CIF]
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The compound described by MgNb4VO12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(3), one O(4), and one O(7) atom. 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(5), and one O(8) atom to form distorted NbO6 octahedra that share corners with four equivalent Nb(4)O6 octahedra and  an edgeedge with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-46°. In the second Nb site, Nb(2) is bonded to one O(1), one O(12), one O(4), one O(6), one O(7), and one O(9) atom to form distorted NbO6 octahedra that share corners with two equivalent Nb(4)O6 octahedra and edges with two equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-40°. In the third Nb site, Nb(3) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(2), one O(4), and one O(9) atom. In the fourth Nb site, Nb(4) is bonded to one O(10), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and corners with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-63°. V(1) is bonded to one O(1), one O(11), one O(4), one O(7), one O(8), and one O(9) atom to form distorted VO6 octahedra that share corners with two equivalent Nb(4)O6 octahedra,  an edgeedge with one Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-63°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Nb(2), one Nb(3), and one V(1) atom to form distorted edge-sharing OMgNb2V trigonal pyramids. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(1), and one Nb(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Nb(2), one Nb(3), and one V(1) atom to form distorted edge-sharing OMgNb2V trigonal pyramids. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(4) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Nb(2) and one Nb(4) atom. In the seventh O site, O(7) is bonded in a distorted see-saw-like geometry to one Mg(1), one Nb(2), one Nb(4), and one V(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(4), and one V(1) atom. In the ninth O site, O(9) is bonded in a T-shaped geometry to one Nb(2), one Nb(3), and one V(1) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(4) atom. In the eleventh O site, O(11) is bonded in a distorted see-saw-like geometry to one Mg(1), one Nb(1), one Nb(3), and one V(1) atom. In the twelfth O site, O(12) is bonded in a T-shaped geometry to one Mg(1), one Nb(2), and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb4VO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.607
_cell_length_b   11.330
_cell_length_c   10.070
_cell_angle_alpha   27.531
_cell_angle_beta   50.916
_cell_angle_gamma   56.016
_symmetry_Int_Tables_number   1
_cell_volume   229.524
_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  0.795  0.507  0.769  1.0
  Nb  Nb1  1  0.018  1.000  0.990  1.0
  Nb  Nb2  1  0.971  0.495  0.015  1.0
  Nb  Nb3  1  0.469  0.998  0.516  1.0
  Nb  Nb4  1  0.520  0.502  0.487  1.0
  V  V5  1  0.296  0.996  0.290  1.0
  O  O6  1  0.366  0.306  0.104  1.0
  O  O7  1  0.233  0.101  0.636  1.0
  O  O8  1  0.093  0.312  0.745  1.0
  O  O9  1  0.855  0.199  0.213  1.0
  O  O10  1  0.337  0.803  0.134  1.0
  O  O11  1  0.733  0.396  0.338  1.0
  O  O12  1  0.212  0.628  0.603  1.0
  O  O13  1  0.596  0.190  0.864  1.0
  O  O14  1  0.127  0.818  0.706  1.0
  O  O15  1  0.842  0.698  0.235  1.0
  O  O16  1  0.711  0.865  0.366  1.0
  O  O17  1  0.636  0.681  0.835  1.0
[/CIF]
.