The structure described by Ba5Ca2Nb3O15 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal I4/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(1), four equivalent O(6), and four equivalent O(7) atoms to form BaO12 cuboctahedra that share corners with twelve equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ca(1)O6 octahedra, and faces with four equivalent Nb(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to one O(2), one O(6), one O(7), two equivalent O(3), two equivalent O(4), two equivalent O(5), and three equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with nine equivalent Ba(2)O12 cuboctahedra,  a faceface with one Ba(1)O12 cuboctahedra, faces with five equivalent Ba(2)O12 cuboctahedra,  a faceface with one Nb(2)O6 octahedra,  a faceface with one Nb(3)O6 octahedra, faces with three equivalent Ca(1)O6 octahedra, and faces with three equivalent Nb(1)O6 octahedra. Ca(1) is bonded to one O(3), one O(5), one O(6), one O(7), and two equivalent O(1) atoms to form CaO6 octahedra that share  a cornercorner with one Nb(2)O6 octahedra, corners with five equivalent Nb(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. There are three inequivalent Nb sites. In the first Nb site, Nb(3) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and faces with eight equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Nb site, Nb(1) is bonded to one O(3), one O(4), one O(6), one O(7), and two equivalent O(1) atoms to form NbO6 octahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with five equivalent Ca(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the third Nb site, Nb(2) is bonded to two equivalent O(2) and four equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(3)O6 octahedra, corners with four equivalent Ca(1)O6 octahedra, and faces with eight equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Ca(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to four equivalent Ba(2), one Nb(2), and one Nb(3) atom. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Ba(2), one Ca(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded to four equivalent Ba(2), one Nb(1), and one Nb(3) atom to form a mixture of distorted corner and face-sharing OBa4Nb2 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent Ba(2), one Ca(1), and one Nb(2) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), one Ca(1), and one Nb(1) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), one Ca(1), and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba5Ca2Nb3O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.507
_cell_length_b   10.507
_cell_length_c   10.507
_cell_angle_alpha   99.476
_cell_angle_beta   99.476
_cell_angle_gamma   132.122
_symmetry_Int_Tables_number   1
_cell_volume   786.248
_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
  Ba  Ba0  1  0.750  0.250  0.500  1.0
  Ba  Ba1  1  0.557  0.656  0.703  1.0
  Ba  Ba2  1  0.953  0.854  0.297  1.0
  Ba  Ba3  1  0.146  0.443  0.099  1.0
  Ba  Ba4  1  0.344  0.047  0.901  1.0
  Ba  Ba5  1  0.854  0.557  0.901  1.0
  Ba  Ba6  1  0.656  0.953  0.099  1.0
  Ba  Ba7  1  0.047  0.146  0.703  1.0
  Ba  Ba8  1  0.250  0.750  0.500  1.0
  Ba  Ba9  1  0.443  0.344  0.297  1.0
  Ca  Ca10  1  0.398  0.202  0.600  1.0
  Ca  Ca11  1  0.798  0.398  0.197  1.0
  Ca  Ca12  1  0.202  0.602  0.803  1.0
  Ca  Ca13  1  0.602  0.798  0.400  1.0
  Nb  Nb14  1  0.306  0.898  0.205  1.0
  Nb  Nb15  1  0.102  0.306  0.408  1.0
  Nb  Nb16  1  0.500  0.500  0.000  1.0
  Nb  Nb17  1  0.694  0.102  0.795  1.0
  Nb  Nb18  1  0.898  0.694  0.592  1.0
  Nb  Nb19  1  0.000  0.000  0.000  1.0
  O  O20  1  0.525  0.136  0.195  1.0
  O  O21  1  0.330  0.525  0.390  1.0
  O  O22  1  0.754  0.754  0.000  1.0
  O  O23  1  0.940  0.330  0.805  1.0
  O  O24  1  0.136  0.940  0.610  1.0
  O  O25  1  0.247  0.764  0.011  1.0
  O  O26  1  0.047  0.142  0.188  1.0
  O  O27  1  0.453  0.362  0.815  1.0
  O  O28  1  0.659  0.958  0.617  1.0
  O  O29  1  0.855  0.559  0.415  1.0
  O  O30  1  0.142  0.953  0.095  1.0
  O  O31  1  0.958  0.341  0.299  1.0
  O  O32  1  0.362  0.547  0.908  1.0
  O  O33  1  0.559  0.145  0.704  1.0
  O  O34  1  0.764  0.753  0.517  1.0
  O  O35  1  0.060  0.670  0.195  1.0
  O  O36  1  0.864  0.060  0.390  1.0
  O  O37  1  0.246  0.246  0.000  1.0
  O  O38  1  0.475  0.864  0.805  1.0
  O  O39  1  0.670  0.475  0.610  1.0
  O  O40  1  0.341  0.042  0.383  1.0
  O  O41  1  0.145  0.441  0.585  1.0
  O  O42  1  0.547  0.638  0.185  1.0
  O  O43  1  0.753  0.236  0.989  1.0
  O  O44  1  0.953  0.858  0.812  1.0
  O  O45  1  0.441  0.855  0.296  1.0
  O  O46  1  0.236  0.247  0.483  1.0
  O  O47  1  0.638  0.453  0.092  1.0
  O  O48  1  0.858  0.047  0.905  1.0
  O  O49  1  0.042  0.659  0.701  1.0
[/CIF]
.
The structure described by Ba5Ca2Nb3O15 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal I4/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(1), four equivalent O(6), and four equivalent O(7) atoms to form BaO12 cuboctahedra that share corners with twelve equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ca(1)O6 octahedra, and faces with four equivalent Nb(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to one O(2), one O(6), one O(7), two equivalent O(3), two equivalent O(4), two equivalent O(5), and three equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with nine equivalent Ba(2)O12 cuboctahedra,  a faceface with one Ba(1)O12 cuboctahedra, faces with five equivalent Ba(2)O12 cuboctahedra,  a faceface with one Nb(2)O6 octahedra,  a faceface with one Nb(3)O6 octahedra, faces with three equivalent Ca(1)O6 octahedra, and faces with three equivalent Nb(1)O6 octahedra. Ca(1) is bonded to one O(3), one O(5), one O(6), one O(7), and two equivalent O(1) atoms to form CaO6 octahedra that share  a cornercorner with one Nb(2)O6 octahedra, corners with five equivalent Nb(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. There are three inequivalent Nb sites. In the first Nb site, Nb(3) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and faces with eight equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Nb site, Nb(1) is bonded to one O(3), one O(4), one O(6), one O(7), and two equivalent O(1) atoms to form NbO6 octahedra that share  a cornercorner with one Nb(3)O6 octahedra, corners with five equivalent Ca(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the third Nb site, Nb(2) is bonded to two equivalent O(2) and four equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(3)O6 octahedra, corners with four equivalent Ca(1)O6 octahedra, and faces with eight equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Ca(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to four equivalent Ba(2), one Nb(2), and one Nb(3) atom. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Ba(2), one Ca(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded to four equivalent Ba(2), one Nb(1), and one Nb(3) atom to form a mixture of distorted corner and face-sharing OBa4Nb2 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent Ba(2), one Ca(1), and one Nb(2) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), one Ca(1), and one Nb(1) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), one Ca(1), and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba5Ca2Nb3O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.507
_cell_length_b   10.507
_cell_length_c   10.507
_cell_angle_alpha   99.476
_cell_angle_beta   99.476
_cell_angle_gamma   132.122
_symmetry_Int_Tables_number   1
_cell_volume   786.248
_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
  Ba  Ba0  1  0.750  0.250  0.500  1.0
  Ba  Ba1  1  0.557  0.656  0.703  1.0
  Ba  Ba2  1  0.953  0.854  0.297  1.0
  Ba  Ba3  1  0.146  0.443  0.099  1.0
  Ba  Ba4  1  0.344  0.047  0.901  1.0
  Ba  Ba5  1  0.854  0.557  0.901  1.0
  Ba  Ba6  1  0.656  0.953  0.099  1.0
  Ba  Ba7  1  0.047  0.146  0.703  1.0
  Ba  Ba8  1  0.250  0.750  0.500  1.0
  Ba  Ba9  1  0.443  0.344  0.297  1.0
  Ca  Ca10  1  0.398  0.202  0.600  1.0
  Ca  Ca11  1  0.798  0.398  0.197  1.0
  Ca  Ca12  1  0.202  0.602  0.803  1.0
  Ca  Ca13  1  0.602  0.798  0.400  1.0
  Nb  Nb14  1  0.306  0.898  0.205  1.0
  Nb  Nb15  1  0.102  0.306  0.408  1.0
  Nb  Nb16  1  0.500  0.500  0.000  1.0
  Nb  Nb17  1  0.694  0.102  0.795  1.0
  Nb  Nb18  1  0.898  0.694  0.592  1.0
  Nb  Nb19  1  0.000  0.000  0.000  1.0
  O  O20  1  0.525  0.136  0.195  1.0
  O  O21  1  0.330  0.525  0.390  1.0
  O  O22  1  0.754  0.754  0.000  1.0
  O  O23  1  0.940  0.330  0.805  1.0
  O  O24  1  0.136  0.940  0.610  1.0
  O  O25  1  0.247  0.764  0.011  1.0
  O  O26  1  0.047  0.142  0.188  1.0
  O  O27  1  0.453  0.362  0.815  1.0
  O  O28  1  0.659  0.958  0.617  1.0
  O  O29  1  0.855  0.559  0.415  1.0
  O  O30  1  0.142  0.953  0.095  1.0
  O  O31  1  0.958  0.341  0.299  1.0
  O  O32  1  0.362  0.547  0.908  1.0
  O  O33  1  0.559  0.145  0.704  1.0
  O  O34  1  0.764  0.753  0.517  1.0
  O  O35  1  0.060  0.670  0.195  1.0
  O  O36  1  0.864  0.060  0.390  1.0
  O  O37  1  0.246  0.246  0.000  1.0
  O  O38  1  0.475  0.864  0.805  1.0
  O  O39  1  0.670  0.475  0.610  1.0
  O  O40  1  0.341  0.042  0.383  1.0
  O  O41  1  0.145  0.441  0.585  1.0
  O  O42  1  0.547  0.638  0.185  1.0
  O  O43  1  0.753  0.236  0.989  1.0
  O  O44  1  0.953  0.858  0.812  1.0
  O  O45  1  0.441  0.855  0.296  1.0
  O  O46  1  0.236  0.247  0.483  1.0
  O  O47  1  0.638  0.453  0.092  1.0
  O  O48  1  0.858  0.047  0.905  1.0
  O  O49  1  0.042  0.659  0.701  1.0
[/CIF]
.