The crystal structure described by MgSc2Nb2O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(4), one O(5), and one O(8) atom. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(5), and one O(7) atom. In the second Sc site, Sc(2) is bonded to one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted ScO5 trigonal bipyramids that share corners with three equivalent Nb(1)O6 octahedra and corners with three equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-62°. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form distorted NbO6 octahedra that share corners with three equivalent Sc(2)O5 trigonal bipyramids and edges with two equivalent Nb(2)O6 octahedra. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form NbO6 octahedra that share corners with three equivalent Sc(2)O5 trigonal bipyramids and edges with two equivalent Nb(1)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Sc(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sc(1), one Nb(1), and one Nb(2) atom. In the third O site, O(3) is bonded to one Mg(1), one Sc(1), one Nb(1), and one Nb(2) atom to form a mixture of distorted corner and edge-sharing OMgScNb2 trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Sc(2), and one Nb(2) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Sc(1), one Sc(2), and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OMgSc2Nb tetrahedra. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sc(2), one Nb(1), and one Nb(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Sc(1), one Sc(2), and one Nb(1) atom. In the eighth O site, O(8) is bonded in a T-shaped geometry to one Mg(1), one Sc(2), and one Nb(2) atom. is represented by the CIF file [CIF]
data_MgSc2Nb2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.309
_cell_length_b   5.277
_cell_length_c   6.217
_cell_angle_alpha   85.807
_cell_angle_beta   96.435
_cell_angle_gamma   104.292
_symmetry_Int_Tables_number   1
_cell_volume   167.499
_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  0.670  0.903  0.338  1.0
  Sc  Sc1  1  0.509  0.792  0.807  1.0
  Sc  Sc2  1  0.429  0.301  0.426  1.0
  Nb  Nb3  1  0.999  0.289  0.855  1.0
  Nb  Nb4  1  0.023  0.700  0.102  1.0
  O  O5  1  0.752  0.530  0.845  1.0
  O  O6  1  0.207  0.944  0.881  1.0
  O  O7  1  0.781  0.001  0.049  1.0
  O  O8  1  0.300  0.931  0.331  1.0
  O  O9  1  0.707  0.081  0.612  1.0
  O  O10  1  0.240  0.428  0.137  1.0
  O  O11  1  0.252  0.449  0.652  1.0
  O  O12  1  0.754  0.563  0.319  1.0
[/CIF]
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The crystal structure described by MgSc2Nb2O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(4), one O(5), and one O(8) atom. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(5), and one O(7) atom. In the second Sc site, Sc(2) is bonded to one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted ScO5 trigonal bipyramids that share corners with three equivalent Nb(1)O6 octahedra and corners with three equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-62°. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form distorted NbO6 octahedra that share corners with three equivalent Sc(2)O5 trigonal bipyramids and edges with two equivalent Nb(2)O6 octahedra. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form NbO6 octahedra that share corners with three equivalent Sc(2)O5 trigonal bipyramids and edges with two equivalent Nb(1)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Sc(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sc(1), one Nb(1), and one Nb(2) atom. In the third O site, O(3) is bonded to one Mg(1), one Sc(1), one Nb(1), and one Nb(2) atom to form a mixture of distorted corner and edge-sharing OMgScNb2 trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Sc(2), and one Nb(2) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Sc(1), one Sc(2), and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OMgSc2Nb tetrahedra. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sc(2), one Nb(1), and one Nb(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Sc(1), one Sc(2), and one Nb(1) atom. In the eighth O site, O(8) is bonded in a T-shaped geometry to one Mg(1), one Sc(2), and one Nb(2) atom. is represented by the CIF file [CIF]
data_MgSc2Nb2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.309
_cell_length_b   5.277
_cell_length_c   6.217
_cell_angle_alpha   85.807
_cell_angle_beta   96.435
_cell_angle_gamma   104.292
_symmetry_Int_Tables_number   1
_cell_volume   167.499
_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  0.670  0.903  0.338  1.0
  Sc  Sc1  1  0.509  0.792  0.807  1.0
  Sc  Sc2  1  0.429  0.301  0.426  1.0
  Nb  Nb3  1  0.999  0.289  0.855  1.0
  Nb  Nb4  1  0.023  0.700  0.102  1.0
  O  O5  1  0.752  0.530  0.845  1.0
  O  O6  1  0.207  0.944  0.881  1.0
  O  O7  1  0.781  0.001  0.049  1.0
  O  O8  1  0.300  0.931  0.331  1.0
  O  O9  1  0.707  0.081  0.612  1.0
  O  O10  1  0.240  0.428  0.137  1.0
  O  O11  1  0.252  0.449  0.652  1.0
  O  O12  1  0.754  0.563  0.319  1.0
[/CIF]
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