The crystal structure described by Sr3CaS4 is Caswellsilverite-like structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form SrS6 octahedra that share corners with six equivalent Sr(1)S6 octahedra, edges with four equivalent Sr(1)S6 octahedra, edges with four equivalent Sr(2)S6 octahedra, and edges with four equivalent Ca(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 2-3°. In the second Sr site, Sr(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form SrS6 octahedra that share corners with six equivalent Ca(1)S6 octahedra, edges with two equivalent Sr(2)S6 octahedra, edges with two equivalent Ca(1)S6 octahedra, and edges with eight equivalent Sr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. Ca(1) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form CaS6 octahedra that share corners with six equivalent Sr(2)S6 octahedra, edges with two equivalent Sr(2)S6 octahedra, edges with two equivalent Ca(1)S6 octahedra, and edges with eight equivalent Sr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Sr(2), four equivalent Sr(1), and one Ca(1) atom to form SSr5Ca octahedra that share corners with six equivalent S(1)Sr5Ca octahedra, edges with four equivalent S(1)Sr5Ca octahedra, and edges with eight equivalent S(2)Sr4Ca2 octahedra. The corner-sharing octahedra are not tilted. In the second S site, S(2) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ca(1) atoms to form SSr4Ca2 octahedra that share corners with six equivalent S(2)Sr4Ca2 octahedra, edges with four equivalent S(2)Sr4Ca2 octahedra, and edges with eight equivalent S(1)Sr5Ca octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3CaS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.308
_cell_length_b   7.308
_cell_length_c   4.220
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.457
_symmetry_Int_Tables_number   1
_cell_volume   212.467
_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  0.000  0.500  0.500  1.0
  Sr  Sr1  1  0.500  0.000  0.500  1.0
  Sr  Sr2  1  0.500  0.500  0.000  1.0
  Ca  Ca3  1  0.000  0.000  0.000  1.0
  S  S4  1  0.246  0.754  0.000  1.0
  S  S5  1  0.754  0.246  0.000  1.0
  S  S6  1  0.759  0.759  0.500  1.0
  S  S7  1  0.241  0.241  0.500  1.0
[/CIF]
.
The crystal structure described by Sr3CaS4 is Caswellsilverite-like structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form SrS6 octahedra that share corners with six equivalent Sr(1)S6 octahedra, edges with four equivalent Sr(1)S6 octahedra, edges with four equivalent Sr(2)S6 octahedra, and edges with four equivalent Ca(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 2-3°. In the second Sr site, Sr(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form SrS6 octahedra that share corners with six equivalent Ca(1)S6 octahedra, edges with two equivalent Sr(2)S6 octahedra, edges with two equivalent Ca(1)S6 octahedra, and edges with eight equivalent Sr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. Ca(1) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form CaS6 octahedra that share corners with six equivalent Sr(2)S6 octahedra, edges with two equivalent Sr(2)S6 octahedra, edges with two equivalent Ca(1)S6 octahedra, and edges with eight equivalent Sr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Sr(2), four equivalent Sr(1), and one Ca(1) atom to form SSr5Ca octahedra that share corners with six equivalent S(1)Sr5Ca octahedra, edges with four equivalent S(1)Sr5Ca octahedra, and edges with eight equivalent S(2)Sr4Ca2 octahedra. The corner-sharing octahedra are not tilted. In the second S site, S(2) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ca(1) atoms to form SSr4Ca2 octahedra that share corners with six equivalent S(2)Sr4Ca2 octahedra, edges with four equivalent S(2)Sr4Ca2 octahedra, and edges with eight equivalent S(1)Sr5Ca octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3CaS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.308
_cell_length_b   7.308
_cell_length_c   4.220
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.457
_symmetry_Int_Tables_number   1
_cell_volume   212.467
_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  0.000  0.500  0.500  1.0
  Sr  Sr1  1  0.500  0.000  0.500  1.0
  Sr  Sr2  1  0.500  0.500  0.000  1.0
  Ca  Ca3  1  0.000  0.000  0.000  1.0
  S  S4  1  0.246  0.754  0.000  1.0
  S  S5  1  0.754  0.246  0.000  1.0
  S  S6  1  0.759  0.759  0.500  1.0
  S  S7  1  0.241  0.241  0.500  1.0
[/CIF]
.