The material described by Mg3V2O7 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(3), and four equivalent O(4) atoms. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to one O(4), two equivalent O(3), and three equivalent O(2) atoms. V(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form corner-sharing VO6 octahedra. The corner-sharing octahedral tilt angles range from 38-42°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1) and two equivalent V(1) atoms to form distorted OMg2V2 tetrahedra that share corners with two equivalent O(1)Mg2V2 tetrahedra and corners with two equivalent O(2)Mg3V tetrahedra. In the second O site, O(2) is bonded to three equivalent Mg(2) and one V(1) atom to form distorted OMg3V tetrahedra that share  a cornercorner with one O(1)Mg2V2 tetrahedra and corners with six equivalent O(2)Mg3V tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mg(2), and two equivalent V(1) atoms. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Mg(2), two equivalent Mg(1), and two equivalent V(1) atoms. is represented by the CIF card [CIF]
data_Mg3V2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.187
_cell_length_b   9.203
_cell_length_c   5.353
_cell_angle_alpha   90.002
_cell_angle_beta   89.990
_cell_angle_gamma   106.373
_symmetry_Int_Tables_number   1
_cell_volume   245.159
_cell_formula_units_Z   2
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  0.753  0.000  0.699  1.0
  Mg  Mg1  1  0.247  0.000  0.200  1.0
  Mg  Mg2  1  0.570  0.615  0.817  1.0
  Mg  Mg3  1  0.430  0.385  0.317  1.0
  Mg  Mg4  1  0.956  0.385  0.817  1.0
  Mg  Mg5  1  0.044  0.615  0.317  1.0
  V  V6  1  0.646  0.790  0.253  1.0
  V  V7  1  0.856  0.210  0.253  1.0
  V  V8  1  0.354  0.210  0.753  1.0
  V  V9  1  0.144  0.790  0.753  1.0
  O  O10  1  0.368  1.000  0.810  1.0
  O  O11  1  0.632  0.000  0.310  1.0
  O  O12  1  0.929  0.590  0.696  1.0
  O  O13  1  0.071  0.410  0.196  1.0
  O  O14  1  0.660  0.590  0.195  1.0
  O  O15  1  0.340  0.410  0.696  1.0
  O  O16  1  0.304  0.738  0.058  1.0
  O  O17  1  0.696  0.262  0.559  1.0
  O  O18  1  0.434  0.738  0.559  1.0
  O  O19  1  0.566  0.262  0.059  1.0
  O  O20  1  0.849  0.843  0.931  1.0
  O  O21  1  0.151  0.157  0.431  1.0
  O  O22  1  0.006  0.157  0.931  1.0
  O  O23  1  0.994  0.843  0.431  1.0
[/CIF]
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The material described by Mg3V2O7 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(3), and four equivalent O(4) atoms. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to one O(4), two equivalent O(3), and three equivalent O(2) atoms. V(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form corner-sharing VO6 octahedra. The corner-sharing octahedral tilt angles range from 38-42°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1) and two equivalent V(1) atoms to form distorted OMg2V2 tetrahedra that share corners with two equivalent O(1)Mg2V2 tetrahedra and corners with two equivalent O(2)Mg3V tetrahedra. In the second O site, O(2) is bonded to three equivalent Mg(2) and one V(1) atom to form distorted OMg3V tetrahedra that share  a cornercorner with one O(1)Mg2V2 tetrahedra and corners with six equivalent O(2)Mg3V tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mg(2), and two equivalent V(1) atoms. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Mg(2), two equivalent Mg(1), and two equivalent V(1) atoms. is represented by the CIF card [CIF]
data_Mg3V2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.187
_cell_length_b   9.203
_cell_length_c   5.353
_cell_angle_alpha   90.002
_cell_angle_beta   89.990
_cell_angle_gamma   106.373
_symmetry_Int_Tables_number   1
_cell_volume   245.159
_cell_formula_units_Z   2
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  0.753  0.000  0.699  1.0
  Mg  Mg1  1  0.247  0.000  0.200  1.0
  Mg  Mg2  1  0.570  0.615  0.817  1.0
  Mg  Mg3  1  0.430  0.385  0.317  1.0
  Mg  Mg4  1  0.956  0.385  0.817  1.0
  Mg  Mg5  1  0.044  0.615  0.317  1.0
  V  V6  1  0.646  0.790  0.253  1.0
  V  V7  1  0.856  0.210  0.253  1.0
  V  V8  1  0.354  0.210  0.753  1.0
  V  V9  1  0.144  0.790  0.753  1.0
  O  O10  1  0.368  1.000  0.810  1.0
  O  O11  1  0.632  0.000  0.310  1.0
  O  O12  1  0.929  0.590  0.696  1.0
  O  O13  1  0.071  0.410  0.196  1.0
  O  O14  1  0.660  0.590  0.195  1.0
  O  O15  1  0.340  0.410  0.696  1.0
  O  O16  1  0.304  0.738  0.058  1.0
  O  O17  1  0.696  0.262  0.559  1.0
  O  O18  1  0.434  0.738  0.559  1.0
  O  O19  1  0.566  0.262  0.059  1.0
  O  O20  1  0.849  0.843  0.931  1.0
  O  O21  1  0.151  0.157  0.431  1.0
  O  O22  1  0.006  0.157  0.931  1.0
  O  O23  1  0.994  0.843  0.431  1.0
[/CIF]
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