The crystal structure described by Sr3CaTi4O12 crystallizes in the monoclinic C2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent O(1), two equivalent O(3), two equivalent O(6), two equivalent O(7), and four equivalent O(4) atoms to form distorted SrO12 cuboctahedra that share corners with six equivalent Sr(1)O12 cuboctahedra, faces with six equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ti(1)O6 octahedra, and faces with six equivalent Ti(2)O6 octahedra. In the second Sr site, Sr(2) is bonded to one O(2), one O(3), two equivalent O(1), two equivalent O(4), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms to form distorted SrO12 cuboctahedra that share corners with twelve equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Ti(2)O6 octahedra. Ca(1) is bonded in a 12-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(6), two equivalent O(7), and four equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(6), one O(7), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra,  a faceface with one Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 10-20°. In the second Ti site, Ti(2) is bonded to one O(1), one O(3), one O(6), one O(7), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra, faces with three equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 7-13°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ca(1), one Ti(1), and one Ti(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ti(2) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ti(2) atoms. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to two equivalent Sr(2), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ca(1), one Ti(1), and one Ti(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ca(1), one Ti(1), and one Ti(2) atom. is represented by the CIF file [CIF]
data_Sr3CaTi4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.547
_cell_length_b   5.547
_cell_length_c   9.599
_cell_angle_alpha   73.394
_cell_angle_beta   73.394
_cell_angle_gamma   60.252
_symmetry_Int_Tables_number   1
_cell_volume   242.041
_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
  Sr  Sr0  1  0.125  0.875  0.500  1.0
  Sr  Sr1  1  0.374  0.126  0.751  1.0
  Sr  Sr2  1  0.874  0.626  0.249  1.0
  Ca  Ca3  1  0.620  0.380  0.000  1.0
  Ti  Ti4  1  0.248  0.003  0.123  1.0
  Ti  Ti5  1  0.748  0.501  0.627  1.0
  Ti  Ti6  1  0.997  0.752  0.877  1.0
  Ti  Ti7  1  0.499  0.252  0.373  1.0
  O  O8  1  0.914  0.585  0.752  1.0
  O  O9  1  0.415  0.086  0.248  1.0
  O  O10  1  0.060  0.940  0.000  1.0
  O  O11  1  0.590  0.410  0.500  1.0
  O  O12  1  0.632  0.882  0.509  1.0
  O  O13  1  0.156  0.384  0.010  1.0
  O  O14  1  0.616  0.844  0.990  1.0
  O  O15  1  0.118  0.368  0.491  1.0
  O  O16  1  0.390  0.630  0.765  1.0
  O  O17  1  0.888  0.132  0.260  1.0
  O  O18  1  0.370  0.610  0.235  1.0
  O  O19  1  0.868  0.112  0.740  1.0
[/CIF]
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The crystal structure described by Sr3CaTi4O12 crystallizes in the monoclinic C2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent O(1), two equivalent O(3), two equivalent O(6), two equivalent O(7), and four equivalent O(4) atoms to form distorted SrO12 cuboctahedra that share corners with six equivalent Sr(1)O12 cuboctahedra, faces with six equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ti(1)O6 octahedra, and faces with six equivalent Ti(2)O6 octahedra. In the second Sr site, Sr(2) is bonded to one O(2), one O(3), two equivalent O(1), two equivalent O(4), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms to form distorted SrO12 cuboctahedra that share corners with twelve equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Ti(2)O6 octahedra. Ca(1) is bonded in a 12-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(6), two equivalent O(7), and four equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(6), one O(7), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra,  a faceface with one Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 10-20°. In the second Ti site, Ti(2) is bonded to one O(1), one O(3), one O(6), one O(7), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra, faces with three equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 7-13°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ca(1), one Ti(1), and one Ti(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ti(2) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ti(2) atoms. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to two equivalent Sr(2), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ca(1), one Ti(1), and one Ti(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ca(1), one Ti(1), and one Ti(2) atom. is represented by the CIF file [CIF]
data_Sr3CaTi4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.547
_cell_length_b   5.547
_cell_length_c   9.599
_cell_angle_alpha   73.394
_cell_angle_beta   73.394
_cell_angle_gamma   60.252
_symmetry_Int_Tables_number   1
_cell_volume   242.041
_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
  Sr  Sr0  1  0.125  0.875  0.500  1.0
  Sr  Sr1  1  0.374  0.126  0.751  1.0
  Sr  Sr2  1  0.874  0.626  0.249  1.0
  Ca  Ca3  1  0.620  0.380  0.000  1.0
  Ti  Ti4  1  0.248  0.003  0.123  1.0
  Ti  Ti5  1  0.748  0.501  0.627  1.0
  Ti  Ti6  1  0.997  0.752  0.877  1.0
  Ti  Ti7  1  0.499  0.252  0.373  1.0
  O  O8  1  0.914  0.585  0.752  1.0
  O  O9  1  0.415  0.086  0.248  1.0
  O  O10  1  0.060  0.940  0.000  1.0
  O  O11  1  0.590  0.410  0.500  1.0
  O  O12  1  0.632  0.882  0.509  1.0
  O  O13  1  0.156  0.384  0.010  1.0
  O  O14  1  0.616  0.844  0.990  1.0
  O  O15  1  0.118  0.368  0.491  1.0
  O  O16  1  0.390  0.630  0.765  1.0
  O  O17  1  0.888  0.132  0.260  1.0
  O  O18  1  0.370  0.610  0.235  1.0
  O  O19  1  0.868  0.112  0.740  1.0
[/CIF]
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