The material described by Ba4(NbSe4)3 crystallizes in the monoclinic P2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Se(1), two equivalent Se(2), two equivalent Se(4), and six equivalent Se(3) atoms to form BaSe12 cuboctahedra that share corners with two equivalent Ba(1)Se12 cuboctahedra, corners with four equivalent Ba(2)Se12 cuboctahedra,  a cornercorner with one Nb(1)Se6 octahedra,  a cornercorner with one Nb(3)Se6 octahedra, corners with two equivalent Nb(2)Se6 octahedra, faces with four equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra,  a faceface with one Nb(1)Se6 octahedra,  a faceface with one Nb(3)Se6 octahedra, and faces with two equivalent Nb(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 18-23°. In the second Ba site, Ba(2) is bonded to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and six equivalent Se(4) atoms to form distorted BaSe12 cuboctahedra that share corners with two equivalent Ba(2)Se12 cuboctahedra, corners with four equivalent Ba(1)Se12 cuboctahedra,  a cornercorner with one Nb(2)Se6 octahedra, corners with two equivalent Nb(1)Se6 octahedra, corners with two equivalent Nb(3)Se6 octahedra, faces with four equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra,  a faceface with one Nb(2)Se6 octahedra, faces with two equivalent Nb(1)Se6 octahedra, and faces with two equivalent Nb(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 20-24°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent Se(1) and four equivalent Se(4) atoms to form NbSe6 octahedra that share corners with two equivalent Ba(1)Se12 cuboctahedra, corners with four equivalent Ba(2)Se12 cuboctahedra, faces with two equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra, and faces with two equivalent Nb(3)Se6 octahedra. In the second Nb site, Nb(2) is bonded to two equivalent Se(2) and four equivalent Se(3) atoms to form NbSe6 octahedra that share corners with two equivalent Ba(2)Se12 cuboctahedra, corners with four equivalent Ba(1)Se12 cuboctahedra, faces with two equivalent Ba(2)Se12 cuboctahedra, and faces with four equivalent Ba(1)Se12 cuboctahedra. In the third Nb site, Nb(3) is bonded to two equivalent Se(1) and four equivalent Se(4) atoms to form NbSe6 octahedra that share corners with two equivalent Ba(1)Se12 cuboctahedra, corners with four equivalent Ba(2)Se12 cuboctahedra, faces with two equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra, and faces with two equivalent Nb(1)Se6 octahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Nb(1), and one Nb(3) atom. In the second Se site, Se(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Nb(2) atom to form a mixture of distorted face, corner, and edge-sharing SeBa4Nb trigonal bipyramids. In the third Se site, Se(3) is bonded to one Ba(2), three equivalent Ba(1), and one Nb(2) atom to form a mixture of distorted face, corner, and edge-sharing SeBa4Nb trigonal bipyramids. In the fourth Se site, Se(4) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nb(1), and one Nb(3) atom. is represented by the CIF card [CIF]
data_Ba4(NbSe4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.894
_cell_length_b   6.027
_cell_length_c   12.707
_cell_angle_alpha   89.816
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   527.966
_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
  Ba  Ba0  1  0.500  0.245  0.151  1.0
  Ba  Ba1  1  0.000  0.244  0.687  1.0
  Ba  Ba2  1  0.000  0.756  0.313  1.0
  Ba  Ba3  1  0.500  0.755  0.849  1.0
  Nb  Nb4  1  0.500  0.500  0.500  1.0
  Nb  Nb5  1  0.000  0.000  0.000  1.0
  Nb  Nb6  1  0.500  0.000  0.500  1.0
  Se  Se7  1  0.500  0.749  0.329  1.0
  Se  Se8  1  0.000  0.749  0.831  1.0
  Se  Se9  1  0.739  0.746  0.084  1.0
  Se  Se10  1  0.236  0.750  0.584  1.0
  Se  Se11  1  0.261  0.746  0.084  1.0
  Se  Se12  1  0.764  0.750  0.584  1.0
  Se  Se13  1  0.000  0.251  0.169  1.0
  Se  Se14  1  0.500  0.251  0.671  1.0
  Se  Se15  1  0.764  0.250  0.416  1.0
  Se  Se16  1  0.261  0.254  0.916  1.0
  Se  Se17  1  0.236  0.250  0.416  1.0
  Se  Se18  1  0.739  0.254  0.916  1.0
[/CIF]
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The material described by Ba4(NbSe4)3 crystallizes in the monoclinic P2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Se(1), two equivalent Se(2), two equivalent Se(4), and six equivalent Se(3) atoms to form BaSe12 cuboctahedra that share corners with two equivalent Ba(1)Se12 cuboctahedra, corners with four equivalent Ba(2)Se12 cuboctahedra,  a cornercorner with one Nb(1)Se6 octahedra,  a cornercorner with one Nb(3)Se6 octahedra, corners with two equivalent Nb(2)Se6 octahedra, faces with four equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra,  a faceface with one Nb(1)Se6 octahedra,  a faceface with one Nb(3)Se6 octahedra, and faces with two equivalent Nb(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 18-23°. In the second Ba site, Ba(2) is bonded to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and six equivalent Se(4) atoms to form distorted BaSe12 cuboctahedra that share corners with two equivalent Ba(2)Se12 cuboctahedra, corners with four equivalent Ba(1)Se12 cuboctahedra,  a cornercorner with one Nb(2)Se6 octahedra, corners with two equivalent Nb(1)Se6 octahedra, corners with two equivalent Nb(3)Se6 octahedra, faces with four equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra,  a faceface with one Nb(2)Se6 octahedra, faces with two equivalent Nb(1)Se6 octahedra, and faces with two equivalent Nb(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 20-24°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent Se(1) and four equivalent Se(4) atoms to form NbSe6 octahedra that share corners with two equivalent Ba(1)Se12 cuboctahedra, corners with four equivalent Ba(2)Se12 cuboctahedra, faces with two equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra, and faces with two equivalent Nb(3)Se6 octahedra. In the second Nb site, Nb(2) is bonded to two equivalent Se(2) and four equivalent Se(3) atoms to form NbSe6 octahedra that share corners with two equivalent Ba(2)Se12 cuboctahedra, corners with four equivalent Ba(1)Se12 cuboctahedra, faces with two equivalent Ba(2)Se12 cuboctahedra, and faces with four equivalent Ba(1)Se12 cuboctahedra. In the third Nb site, Nb(3) is bonded to two equivalent Se(1) and four equivalent Se(4) atoms to form NbSe6 octahedra that share corners with two equivalent Ba(1)Se12 cuboctahedra, corners with four equivalent Ba(2)Se12 cuboctahedra, faces with two equivalent Ba(1)Se12 cuboctahedra, faces with four equivalent Ba(2)Se12 cuboctahedra, and faces with two equivalent Nb(1)Se6 octahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Nb(1), and one Nb(3) atom. In the second Se site, Se(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Nb(2) atom to form a mixture of distorted face, corner, and edge-sharing SeBa4Nb trigonal bipyramids. In the third Se site, Se(3) is bonded to one Ba(2), three equivalent Ba(1), and one Nb(2) atom to form a mixture of distorted face, corner, and edge-sharing SeBa4Nb trigonal bipyramids. In the fourth Se site, Se(4) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nb(1), and one Nb(3) atom. is represented by the CIF card [CIF]
data_Ba4(NbSe4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.894
_cell_length_b   6.027
_cell_length_c   12.707
_cell_angle_alpha   89.816
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   527.966
_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
  Ba  Ba0  1  0.500  0.245  0.151  1.0
  Ba  Ba1  1  0.000  0.244  0.687  1.0
  Ba  Ba2  1  0.000  0.756  0.313  1.0
  Ba  Ba3  1  0.500  0.755  0.849  1.0
  Nb  Nb4  1  0.500  0.500  0.500  1.0
  Nb  Nb5  1  0.000  0.000  0.000  1.0
  Nb  Nb6  1  0.500  0.000  0.500  1.0
  Se  Se7  1  0.500  0.749  0.329  1.0
  Se  Se8  1  0.000  0.749  0.831  1.0
  Se  Se9  1  0.739  0.746  0.084  1.0
  Se  Se10  1  0.236  0.750  0.584  1.0
  Se  Se11  1  0.261  0.746  0.084  1.0
  Se  Se12  1  0.764  0.750  0.584  1.0
  Se  Se13  1  0.000  0.251  0.169  1.0
  Se  Se14  1  0.500  0.251  0.671  1.0
  Se  Se15  1  0.764  0.250  0.416  1.0
  Se  Se16  1  0.261  0.254  0.916  1.0
  Se  Se17  1  0.236  0.250  0.416  1.0
  Se  Se18  1  0.739  0.254  0.916  1.0
[/CIF]
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