The crystal structure described by Ba4CaTi5O15 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(2), four equivalent O(4), and four equivalent O(5) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, corners with four equivalent Ba(2)O12 cuboctahedra, corners with four equivalent Ca(1)O12 cuboctahedra,  a faceface with one Ba(2)O12 cuboctahedra,  a faceface with one Ca(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Ti(2)O6 octahedra. In the second Ba site, Ba(2) is bonded to four equivalent O(3), four equivalent O(5), and four equivalent O(6) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, corners with eight equivalent Ba(2)O12 cuboctahedra,  a faceface with one Ba(1)O12 cuboctahedra, faces with five equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ti(2)O6 octahedra, and faces with four equivalent Ti(3)O6 octahedra. Ca(1) is bonded to four equivalent O(1) and eight equivalent O(4) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(2)O6 octahedra, corners with five equivalent Ti(1)O6 octahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with four equivalent Ca(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Ti site, Ti(2) is bonded to one O(2), one O(3), and four equivalent O(5) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra, corners with four equivalent Ti(2)O6 octahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with four equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third Ti site, Ti(3) is bonded to two equivalent O(3) and four equivalent O(6) atoms to form TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with four equivalent Ti(3)O6 octahedra, and faces with eight equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are six inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to four equivalent Ca(1) and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded to four equivalent Ba(1), one Ti(1), and one Ti(2) atom to form a mixture of distorted corner and edge-sharing OBa4Ti2 octahedra. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Ba(2), one Ti(2), and one Ti(3) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ti(2) atoms. In the sixth O site, O(6) is bonded in a distorted linear geometry to four equivalent Ba(2) and two equivalent Ti(3) atoms. is represented by the CIF file [CIF]
data_Ba4CaTi5O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.009
_cell_length_b   4.009
_cell_length_c   20.038
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   322.062
_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  0.000  0.000  0.198  1.0
  Ba  Ba1  1  0.000  0.000  0.400  1.0
  Ba  Ba2  1  0.000  0.000  0.600  1.0
  Ba  Ba3  1  0.000  0.000  0.802  1.0
  Ca  Ca4  1  0.000  0.000  0.000  1.0
  Ti  Ti5  1  0.500  0.500  0.096  1.0
  Ti  Ti6  1  0.500  0.500  0.299  1.0
  Ti  Ti7  1  0.500  0.500  0.500  1.0
  Ti  Ti8  1  0.500  0.500  0.701  1.0
  Ti  Ti9  1  0.500  0.500  0.904  1.0
  O  O10  1  0.500  0.500  0.000  1.0
  O  O11  1  0.500  0.500  0.198  1.0
  O  O12  1  0.500  0.500  0.400  1.0
  O  O13  1  0.500  0.500  0.600  1.0
  O  O14  1  0.500  0.500  0.802  1.0
  O  O15  1  0.500  0.000  0.093  1.0
  O  O16  1  0.500  0.000  0.300  1.0
  O  O17  1  0.500  0.000  0.500  1.0
  O  O18  1  0.500  0.000  0.700  1.0
  O  O19  1  0.500  0.000  0.907  1.0
  O  O20  1  0.000  0.500  0.093  1.0
  O  O21  1  0.000  0.500  0.300  1.0
  O  O22  1  0.000  0.500  0.500  1.0
  O  O23  1  0.000  0.500  0.700  1.0
  O  O24  1  0.000  0.500  0.907  1.0
[/CIF]
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The crystal structure described by Ba4CaTi5O15 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(2), four equivalent O(4), and four equivalent O(5) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, corners with four equivalent Ba(2)O12 cuboctahedra, corners with four equivalent Ca(1)O12 cuboctahedra,  a faceface with one Ba(2)O12 cuboctahedra,  a faceface with one Ca(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Ti(2)O6 octahedra. In the second Ba site, Ba(2) is bonded to four equivalent O(3), four equivalent O(5), and four equivalent O(6) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, corners with eight equivalent Ba(2)O12 cuboctahedra,  a faceface with one Ba(1)O12 cuboctahedra, faces with five equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ti(2)O6 octahedra, and faces with four equivalent Ti(3)O6 octahedra. Ca(1) is bonded to four equivalent O(1) and eight equivalent O(4) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(2)O6 octahedra, corners with five equivalent Ti(1)O6 octahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with four equivalent Ca(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Ti site, Ti(2) is bonded to one O(2), one O(3), and four equivalent O(5) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra, corners with four equivalent Ti(2)O6 octahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with four equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third Ti site, Ti(3) is bonded to two equivalent O(3) and four equivalent O(6) atoms to form TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with four equivalent Ti(3)O6 octahedra, and faces with eight equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are six inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to four equivalent Ca(1) and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded to four equivalent Ba(1), one Ti(1), and one Ti(2) atom to form a mixture of distorted corner and edge-sharing OBa4Ti2 octahedra. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Ba(2), one Ti(2), and one Ti(3) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ti(2) atoms. In the sixth O site, O(6) is bonded in a distorted linear geometry to four equivalent Ba(2) and two equivalent Ti(3) atoms. is represented by the CIF file [CIF]
data_Ba4CaTi5O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.009
_cell_length_b   4.009
_cell_length_c   20.038
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   322.062
_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  0.000  0.000  0.198  1.0
  Ba  Ba1  1  0.000  0.000  0.400  1.0
  Ba  Ba2  1  0.000  0.000  0.600  1.0
  Ba  Ba3  1  0.000  0.000  0.802  1.0
  Ca  Ca4  1  0.000  0.000  0.000  1.0
  Ti  Ti5  1  0.500  0.500  0.096  1.0
  Ti  Ti6  1  0.500  0.500  0.299  1.0
  Ti  Ti7  1  0.500  0.500  0.500  1.0
  Ti  Ti8  1  0.500  0.500  0.701  1.0
  Ti  Ti9  1  0.500  0.500  0.904  1.0
  O  O10  1  0.500  0.500  0.000  1.0
  O  O11  1  0.500  0.500  0.198  1.0
  O  O12  1  0.500  0.500  0.400  1.0
  O  O13  1  0.500  0.500  0.600  1.0
  O  O14  1  0.500  0.500  0.802  1.0
  O  O15  1  0.500  0.000  0.093  1.0
  O  O16  1  0.500  0.000  0.300  1.0
  O  O17  1  0.500  0.000  0.500  1.0
  O  O18  1  0.500  0.000  0.700  1.0
  O  O19  1  0.500  0.000  0.907  1.0
  O  O20  1  0.000  0.500  0.093  1.0
  O  O21  1  0.000  0.500  0.300  1.0
  O  O22  1  0.000  0.500  0.500  1.0
  O  O23  1  0.000  0.500  0.700  1.0
  O  O24  1  0.000  0.500  0.907  1.0
[/CIF]
.