The material structure described by Sm3NbO7 crystallizes in the triclinic P-1 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to one O(3), one O(4), one O(7), two equivalent O(2), and two equivalent O(6) atoms to form distorted SmO7 pentagonal bipyramids that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Sm(3)O7 pentagonal bipyramid,  an edgeedge with one Nb(1)O6 octahedra, edges with two equivalent Sm(1)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 48-50°. In the second Sm site, Sm(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(6), two equivalent O(4), and two equivalent O(7) atoms. In the third Sm site, Sm(3) is bonded to one O(5), one O(6), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form distorted SmO7 pentagonal bipyramids that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Sm(1)O7 pentagonal bipyramid,  an edgeedge with one Nb(1)O6 octahedra,  an edgeedge with one Nb(2)O6 octahedra, edges with two equivalent Sm(1)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 44-45°. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Sm(1)O7 pentagonal bipyramids, corners with two equivalent Sm(3)O7 pentagonal bipyramids, edges with two equivalent Sm(1)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 32°. In the second Nb site, Nb(2) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Sm(1)O7 pentagonal bipyramids, corners with two equivalent Sm(3)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 32°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Sm(2), two equivalent Sm(3), and one Nb(2) atom to form distorted OSm3Nb tetrahedra that share  a cornercorner with one O(1)Sm3Nb tetrahedra,  a cornercorner with one O(6)Sm4 tetrahedra, corners with two equivalent O(4)Sm3Nb tetrahedra, corners with two equivalent O(7)Sm4 tetrahedra, corners with four equivalent O(3)Sm3Nb tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(4)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(1), and one Nb(1) atom. In the third O site, O(3) is bonded to one Sm(1), two equivalent Sm(3), and one Nb(1) atom to form distorted OSm3Nb tetrahedra that share  a cornercorner with one O(3)Sm3Nb tetrahedra,  a cornercorner with one O(4)Sm3Nb tetrahedra,  a cornercorner with one O(7)Sm4 tetrahedra, corners with two equivalent O(6)Sm4 tetrahedra, corners with four equivalent O(1)Sm3Nb tetrahedra,  an edgeedge with one O(3)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the fourth O site, O(4) is bonded to one Sm(1), two equivalent Sm(2), and one Nb(2) atom to form distorted OSm3Nb tetrahedra that share  a cornercorner with one O(3)Sm3Nb tetrahedra,  a cornercorner with one O(4)Sm3Nb tetrahedra, corners with two equivalent O(1)Sm3Nb tetrahedra, corners with three equivalent O(7)Sm4 tetrahedra, corners with four equivalent O(6)Sm4 tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(4)Sm3Nb tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sm(3), one Nb(1), and one Nb(2) atom. In the sixth O site, O(6) is bonded to one Sm(2), one Sm(3), and two equivalent Sm(1) atoms to form OSm4 tetrahedra that share  a cornercorner with one O(1)Sm3Nb tetrahedra, corners with two equivalent O(3)Sm3Nb tetrahedra, corners with three equivalent O(7)Sm4 tetrahedra, corners with four equivalent O(4)Sm3Nb tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(3)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the seventh O site, O(7) is bonded to one Sm(1), one Sm(3), and two equivalent Sm(2) atoms to form OSm4 tetrahedra that share  a cornercorner with one O(3)Sm3Nb tetrahedra, corners with two equivalent O(1)Sm3Nb tetrahedra, corners with three equivalent O(4)Sm3Nb tetrahedra, corners with three equivalent O(6)Sm4 tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(3)Sm3Nb tetrahedra,  an edgeedge with one O(4)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. is represented by the CIF card [CIF]
data_Sm3NbO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.480
_cell_length_b   6.593
_cell_length_c   7.709
_cell_angle_alpha   106.846
_cell_angle_beta   89.825
_cell_angle_gamma   97.373
_symmetry_Int_Tables_number   1
_cell_volume   312.396
_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
  Sm  Sm0  1  0.738  0.464  0.117  1.0
  Sm  Sm1  1  0.739  0.460  0.610  1.0
  Sm  Sm2  1  0.547  0.993  0.750  1.0
  Sm  Sm3  1  0.453  0.007  0.250  1.0
  Sm  Sm4  1  0.261  0.540  0.390  1.0
  Sm  Sm5  1  0.262  0.536  0.883  1.0
  Nb  Nb6  1  0.000  0.000  0.000  1.0
  Nb  Nb7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.712  0.069  0.485  1.0
  O  O9  1  0.922  0.680  0.944  1.0
  O  O10  1  0.711  0.070  0.049  1.0
  O  O11  1  0.924  0.674  0.398  1.0
  O  O12  1  0.917  0.961  0.739  1.0
  O  O13  1  0.558  0.351  0.835  1.0
  O  O14  1  0.545  0.363  0.342  1.0
  O  O15  1  0.455  0.637  0.658  1.0
  O  O16  1  0.442  0.649  0.165  1.0
  O  O17  1  0.083  0.039  0.261  1.0
  O  O18  1  0.076  0.326  0.602  1.0
  O  O19  1  0.289  0.930  0.951  1.0
  O  O20  1  0.078  0.320  0.056  1.0
  O  O21  1  0.288  0.931  0.515  1.0
[/CIF]
.
The material structure described by Sm3NbO7 crystallizes in the triclinic P-1 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to one O(3), one O(4), one O(7), two equivalent O(2), and two equivalent O(6) atoms to form distorted SmO7 pentagonal bipyramids that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Sm(3)O7 pentagonal bipyramid,  an edgeedge with one Nb(1)O6 octahedra, edges with two equivalent Sm(1)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 48-50°. In the second Sm site, Sm(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(6), two equivalent O(4), and two equivalent O(7) atoms. In the third Sm site, Sm(3) is bonded to one O(5), one O(6), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form distorted SmO7 pentagonal bipyramids that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Sm(1)O7 pentagonal bipyramid,  an edgeedge with one Nb(1)O6 octahedra,  an edgeedge with one Nb(2)O6 octahedra, edges with two equivalent Sm(1)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 44-45°. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Sm(1)O7 pentagonal bipyramids, corners with two equivalent Sm(3)O7 pentagonal bipyramids, edges with two equivalent Sm(1)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 32°. In the second Nb site, Nb(2) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Sm(1)O7 pentagonal bipyramids, corners with two equivalent Sm(3)O7 pentagonal bipyramids, and edges with two equivalent Sm(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 32°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Sm(2), two equivalent Sm(3), and one Nb(2) atom to form distorted OSm3Nb tetrahedra that share  a cornercorner with one O(1)Sm3Nb tetrahedra,  a cornercorner with one O(6)Sm4 tetrahedra, corners with two equivalent O(4)Sm3Nb tetrahedra, corners with two equivalent O(7)Sm4 tetrahedra, corners with four equivalent O(3)Sm3Nb tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(4)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(1), and one Nb(1) atom. In the third O site, O(3) is bonded to one Sm(1), two equivalent Sm(3), and one Nb(1) atom to form distorted OSm3Nb tetrahedra that share  a cornercorner with one O(3)Sm3Nb tetrahedra,  a cornercorner with one O(4)Sm3Nb tetrahedra,  a cornercorner with one O(7)Sm4 tetrahedra, corners with two equivalent O(6)Sm4 tetrahedra, corners with four equivalent O(1)Sm3Nb tetrahedra,  an edgeedge with one O(3)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the fourth O site, O(4) is bonded to one Sm(1), two equivalent Sm(2), and one Nb(2) atom to form distorted OSm3Nb tetrahedra that share  a cornercorner with one O(3)Sm3Nb tetrahedra,  a cornercorner with one O(4)Sm3Nb tetrahedra, corners with two equivalent O(1)Sm3Nb tetrahedra, corners with three equivalent O(7)Sm4 tetrahedra, corners with four equivalent O(6)Sm4 tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(4)Sm3Nb tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sm(3), one Nb(1), and one Nb(2) atom. In the sixth O site, O(6) is bonded to one Sm(2), one Sm(3), and two equivalent Sm(1) atoms to form OSm4 tetrahedra that share  a cornercorner with one O(1)Sm3Nb tetrahedra, corners with two equivalent O(3)Sm3Nb tetrahedra, corners with three equivalent O(7)Sm4 tetrahedra, corners with four equivalent O(4)Sm3Nb tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(3)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. In the seventh O site, O(7) is bonded to one Sm(1), one Sm(3), and two equivalent Sm(2) atoms to form OSm4 tetrahedra that share  a cornercorner with one O(3)Sm3Nb tetrahedra, corners with two equivalent O(1)Sm3Nb tetrahedra, corners with three equivalent O(4)Sm3Nb tetrahedra, corners with three equivalent O(6)Sm4 tetrahedra,  an edgeedge with one O(1)Sm3Nb tetrahedra,  an edgeedge with one O(3)Sm3Nb tetrahedra,  an edgeedge with one O(4)Sm3Nb tetrahedra,  an edgeedge with one O(6)Sm4 tetrahedra, and  an edgeedge with one O(7)Sm4 tetrahedra. is represented by the CIF card [CIF]
data_Sm3NbO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.480
_cell_length_b   6.593
_cell_length_c   7.709
_cell_angle_alpha   106.846
_cell_angle_beta   89.825
_cell_angle_gamma   97.373
_symmetry_Int_Tables_number   1
_cell_volume   312.396
_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
  Sm  Sm0  1  0.738  0.464  0.117  1.0
  Sm  Sm1  1  0.739  0.460  0.610  1.0
  Sm  Sm2  1  0.547  0.993  0.750  1.0
  Sm  Sm3  1  0.453  0.007  0.250  1.0
  Sm  Sm4  1  0.261  0.540  0.390  1.0
  Sm  Sm5  1  0.262  0.536  0.883  1.0
  Nb  Nb6  1  0.000  0.000  0.000  1.0
  Nb  Nb7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.712  0.069  0.485  1.0
  O  O9  1  0.922  0.680  0.944  1.0
  O  O10  1  0.711  0.070  0.049  1.0
  O  O11  1  0.924  0.674  0.398  1.0
  O  O12  1  0.917  0.961  0.739  1.0
  O  O13  1  0.558  0.351  0.835  1.0
  O  O14  1  0.545  0.363  0.342  1.0
  O  O15  1  0.455  0.637  0.658  1.0
  O  O16  1  0.442  0.649  0.165  1.0
  O  O17  1  0.083  0.039  0.261  1.0
  O  O18  1  0.076  0.326  0.602  1.0
  O  O19  1  0.289  0.930  0.951  1.0
  O  O20  1  0.078  0.320  0.056  1.0
  O  O21  1  0.288  0.931  0.515  1.0
[/CIF]
.