The structure described by MgNd2(BiO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share edges with two equivalent Bi(1)O6 octahedra. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Nd site, Nd(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(2) atom. In the third O site, O(3) is bonded to one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2Bi2 tetrahedra that share corners with four equivalent O(5)Nd2Bi2 tetrahedra, edges with two equivalent O(4)Nd2MgBi2 trigonal bipyramids, and edges with two equivalent O(6)Nd2MgBi2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one Mg(1), one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2MgBi2 trigonal bipyramids that share corners with three equivalent O(6)Nd2MgBi2 trigonal bipyramids, edges with two equivalent O(3)Nd2Bi2 tetrahedra, edges with two equivalent O(5)Nd2Bi2 tetrahedra, and  an edgeedge with one O(6)Nd2MgBi2 trigonal bipyramid. In the fifth O site, O(5) is bonded to one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2Bi2 tetrahedra that share corners with four equivalent O(3)Nd2Bi2 tetrahedra, edges with two equivalent O(4)Nd2MgBi2 trigonal bipyramids, and edges with two equivalent O(6)Nd2MgBi2 trigonal bipyramids. In the sixth O site, O(6) is bonded to one Mg(1), one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2MgBi2 trigonal bipyramids that share corners with three equivalent O(4)Nd2MgBi2 trigonal bipyramids, edges with two equivalent O(3)Nd2Bi2 tetrahedra, edges with two equivalent O(5)Nd2Bi2 tetrahedra, and  an edgeedge with one O(4)Nd2MgBi2 trigonal bipyramid. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nd2Mg(BiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.506
_cell_length_b   7.507
_cell_length_c   7.103
_cell_angle_alpha   134.692
_cell_angle_beta   133.117
_cell_angle_gamma   71.809
_symmetry_Int_Tables_number   1
_cell_volume   196.449
_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
  Nd  Nd0  1  0.375  0.123  0.251  1.0
  Nd  Nd1  1  0.619  0.868  0.750  1.0
  Mg  Mg2  1  0.927  0.175  0.750  1.0
  Bi  Bi3  1  0.826  0.575  0.250  1.0
  Bi  Bi4  1  0.160  0.410  0.750  1.0
  O  O5  1  0.749  0.479  0.837  1.0
  O  O6  1  0.775  0.108  0.318  1.0
  O  O7  1  0.480  0.216  0.766  1.0
  O  O8  1  0.003  0.262  0.171  1.0
  O  O9  1  0.951  0.713  0.734  1.0
  O  O10  1  0.591  0.830  0.328  1.0
  O  O11  1  0.143  0.912  0.664  1.0
  O  O12  1  0.290  0.458  0.182  1.0
[/CIF]
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The structure described by MgNd2(BiO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share edges with two equivalent Bi(1)O6 octahedra. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Nd site, Nd(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(2) atom. In the third O site, O(3) is bonded to one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2Bi2 tetrahedra that share corners with four equivalent O(5)Nd2Bi2 tetrahedra, edges with two equivalent O(4)Nd2MgBi2 trigonal bipyramids, and edges with two equivalent O(6)Nd2MgBi2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one Mg(1), one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2MgBi2 trigonal bipyramids that share corners with three equivalent O(6)Nd2MgBi2 trigonal bipyramids, edges with two equivalent O(3)Nd2Bi2 tetrahedra, edges with two equivalent O(5)Nd2Bi2 tetrahedra, and  an edgeedge with one O(6)Nd2MgBi2 trigonal bipyramid. In the fifth O site, O(5) is bonded to one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2Bi2 tetrahedra that share corners with four equivalent O(3)Nd2Bi2 tetrahedra, edges with two equivalent O(4)Nd2MgBi2 trigonal bipyramids, and edges with two equivalent O(6)Nd2MgBi2 trigonal bipyramids. In the sixth O site, O(6) is bonded to one Mg(1), one Nd(1), one Nd(2), one Bi(1), and one Bi(2) atom to form distorted ONd2MgBi2 trigonal bipyramids that share corners with three equivalent O(4)Nd2MgBi2 trigonal bipyramids, edges with two equivalent O(3)Nd2Bi2 tetrahedra, edges with two equivalent O(5)Nd2Bi2 tetrahedra, and  an edgeedge with one O(4)Nd2MgBi2 trigonal bipyramid. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Mg(1), one Nd(1), one Nd(2), and one Bi(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nd2Mg(BiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.506
_cell_length_b   7.507
_cell_length_c   7.103
_cell_angle_alpha   134.692
_cell_angle_beta   133.117
_cell_angle_gamma   71.809
_symmetry_Int_Tables_number   1
_cell_volume   196.449
_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
  Nd  Nd0  1  0.375  0.123  0.251  1.0
  Nd  Nd1  1  0.619  0.868  0.750  1.0
  Mg  Mg2  1  0.927  0.175  0.750  1.0
  Bi  Bi3  1  0.826  0.575  0.250  1.0
  Bi  Bi4  1  0.160  0.410  0.750  1.0
  O  O5  1  0.749  0.479  0.837  1.0
  O  O6  1  0.775  0.108  0.318  1.0
  O  O7  1  0.480  0.216  0.766  1.0
  O  O8  1  0.003  0.262  0.171  1.0
  O  O9  1  0.951  0.713  0.734  1.0
  O  O10  1  0.591  0.830  0.328  1.0
  O  O11  1  0.143  0.912  0.664  1.0
  O  O12  1  0.290  0.458  0.182  1.0
[/CIF]
.