The structure described by Sr3Ca(NCl)2 is Caswellsilverite-derived structured and crystallizes in the monoclinic Cm space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one N(1), two equivalent N(2), one Cl(2), and two equivalent Cl(1) atoms to form SrN3Cl3 octahedra that share corners with three equivalent Sr(2)N3Cl3 octahedra, corners with three equivalent Sr(3)N3Cl3 octahedra, edges with two equivalent Sr(1)N3Cl3 octahedra, edges with three equivalent Sr(2)N3Cl3 octahedra, edges with three equivalent Sr(3)N3Cl3 octahedra, and edges with four equivalent Ca(1)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Sr site, Sr(2) is bonded to one N(2), two equivalent N(1), one Cl(2), and two equivalent Cl(1) atoms to form distorted SrN3Cl3 octahedra that share corners with three equivalent Sr(1)N3Cl3 octahedra, corners with three equivalent Ca(1)N3Cl3 octahedra, edges with two equivalent Sr(2)N3Cl3 octahedra, edges with three equivalent Sr(1)N3Cl3 octahedra, edges with three equivalent Ca(1)N3Cl3 octahedra, and edges with four equivalent Sr(3)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the third Sr site, Sr(3) is bonded to one N(1), two equivalent N(2), one Cl(1), and two equivalent Cl(2) atoms to form distorted SrN3Cl3 octahedra that share corners with three equivalent Sr(1)N3Cl3 octahedra, corners with three equivalent Ca(1)N3Cl3 octahedra, edges with two equivalent Sr(3)N3Cl3 octahedra, edges with three equivalent Sr(1)N3Cl3 octahedra, edges with three equivalent Ca(1)N3Cl3 octahedra, and edges with four equivalent Sr(2)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. Ca(1) is bonded to one N(2), two equivalent N(1), one Cl(1), and two equivalent Cl(2) atoms to form distorted CaN3Cl3 octahedra that share corners with three equivalent Sr(2)N3Cl3 octahedra, corners with three equivalent Sr(3)N3Cl3 octahedra, edges with two equivalent Ca(1)N3Cl3 octahedra, edges with three equivalent Sr(2)N3Cl3 octahedra, edges with three equivalent Sr(3)N3Cl3 octahedra, and edges with four equivalent Sr(1)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Sr(1), one Sr(3), two equivalent Sr(2), and two equivalent Ca(1) atoms to form NSr4Ca2 octahedra that share corners with three equivalent Cl(2)Sr4Ca2 octahedra, corners with three equivalent Cl(1)Sr5Ca octahedra, edges with two equivalent N(1)Sr4Ca2 octahedra, edges with three equivalent Cl(2)Sr4Ca2 octahedra, edges with three equivalent Cl(1)Sr5Ca octahedra, and edges with four equivalent N(2)Sr5Ca octahedra. The corner-sharing octahedral tilt angles range from 11-17°. In the second N site, N(2) is bonded to one Sr(2), two equivalent Sr(1), two equivalent Sr(3), and one Ca(1) atom to form NSr5Ca octahedra that share corners with three equivalent Cl(2)Sr4Ca2 octahedra, corners with three equivalent Cl(1)Sr5Ca octahedra, edges with two equivalent N(2)Sr5Ca octahedra, edges with three equivalent Cl(2)Sr4Ca2 octahedra, edges with three equivalent Cl(1)Sr5Ca octahedra, and edges with four equivalent N(1)Sr4Ca2 octahedra. The corner-sharing octahedral tilt angles range from 12-17°. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to one Sr(3), two equivalent Sr(1), two equivalent Sr(2), and one Ca(1) atom to form distorted ClSr5Ca octahedra that share corners with three equivalent N(1)Sr4Ca2 octahedra, corners with three equivalent N(2)Sr5Ca octahedra, edges with two equivalent Cl(1)Sr5Ca octahedra, edges with three equivalent N(1)Sr4Ca2 octahedra, edges with three equivalent N(2)Sr5Ca octahedra, and edges with four equivalent Cl(2)Sr4Ca2 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. In the second Cl site, Cl(2) is bonded to one Sr(1), one Sr(2), two equivalent Sr(3), and two equivalent Ca(1) atoms to form distorted ClSr4Ca2 octahedra that share corners with three equivalent N(1)Sr4Ca2 octahedra, corners with three equivalent N(2)Sr5Ca octahedra, edges with two equivalent Cl(2)Sr4Ca2 octahedra, edges with three equivalent N(1)Sr4Ca2 octahedra, edges with three equivalent N(2)Sr5Ca octahedra, and edges with four equivalent Cl(1)Sr5Ca octahedra. The corner-sharing octahedral tilt angles range from 12-17°. is represented by the CIF file [CIF]
data_Sr3Ca(NCl)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.368
_cell_length_b   7.368
_cell_length_c   6.673
_cell_angle_alpha   81.343
_cell_angle_beta   81.343
_cell_angle_gamma   30.299
_symmetry_Int_Tables_number   1
_cell_volume   180.518
_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  0.850  0.850  0.381  1.0
  Sr  Sr1  1  0.157  0.157  0.615  1.0
  Sr  Sr2  1  0.654  0.654  0.115  1.0
  Ca  Ca3  1  0.338  0.338  0.890  1.0
  N  N4  1  0.754  0.754  0.755  1.0
  N  N5  1  0.252  0.252  0.243  1.0
  Cl  Cl6  1  0.500  0.500  0.508  1.0
  Cl  Cl7  1  0.996  0.996  0.993  1.0
[/CIF]
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The structure described by Sr3Ca(NCl)2 is Caswellsilverite-derived structured and crystallizes in the monoclinic Cm space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one N(1), two equivalent N(2), one Cl(2), and two equivalent Cl(1) atoms to form SrN3Cl3 octahedra that share corners with three equivalent Sr(2)N3Cl3 octahedra, corners with three equivalent Sr(3)N3Cl3 octahedra, edges with two equivalent Sr(1)N3Cl3 octahedra, edges with three equivalent Sr(2)N3Cl3 octahedra, edges with three equivalent Sr(3)N3Cl3 octahedra, and edges with four equivalent Ca(1)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Sr site, Sr(2) is bonded to one N(2), two equivalent N(1), one Cl(2), and two equivalent Cl(1) atoms to form distorted SrN3Cl3 octahedra that share corners with three equivalent Sr(1)N3Cl3 octahedra, corners with three equivalent Ca(1)N3Cl3 octahedra, edges with two equivalent Sr(2)N3Cl3 octahedra, edges with three equivalent Sr(1)N3Cl3 octahedra, edges with three equivalent Ca(1)N3Cl3 octahedra, and edges with four equivalent Sr(3)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the third Sr site, Sr(3) is bonded to one N(1), two equivalent N(2), one Cl(1), and two equivalent Cl(2) atoms to form distorted SrN3Cl3 octahedra that share corners with three equivalent Sr(1)N3Cl3 octahedra, corners with three equivalent Ca(1)N3Cl3 octahedra, edges with two equivalent Sr(3)N3Cl3 octahedra, edges with three equivalent Sr(1)N3Cl3 octahedra, edges with three equivalent Ca(1)N3Cl3 octahedra, and edges with four equivalent Sr(2)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. Ca(1) is bonded to one N(2), two equivalent N(1), one Cl(1), and two equivalent Cl(2) atoms to form distorted CaN3Cl3 octahedra that share corners with three equivalent Sr(2)N3Cl3 octahedra, corners with three equivalent Sr(3)N3Cl3 octahedra, edges with two equivalent Ca(1)N3Cl3 octahedra, edges with three equivalent Sr(2)N3Cl3 octahedra, edges with three equivalent Sr(3)N3Cl3 octahedra, and edges with four equivalent Sr(1)N3Cl3 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Sr(1), one Sr(3), two equivalent Sr(2), and two equivalent Ca(1) atoms to form NSr4Ca2 octahedra that share corners with three equivalent Cl(2)Sr4Ca2 octahedra, corners with three equivalent Cl(1)Sr5Ca octahedra, edges with two equivalent N(1)Sr4Ca2 octahedra, edges with three equivalent Cl(2)Sr4Ca2 octahedra, edges with three equivalent Cl(1)Sr5Ca octahedra, and edges with four equivalent N(2)Sr5Ca octahedra. The corner-sharing octahedral tilt angles range from 11-17°. In the second N site, N(2) is bonded to one Sr(2), two equivalent Sr(1), two equivalent Sr(3), and one Ca(1) atom to form NSr5Ca octahedra that share corners with three equivalent Cl(2)Sr4Ca2 octahedra, corners with three equivalent Cl(1)Sr5Ca octahedra, edges with two equivalent N(2)Sr5Ca octahedra, edges with three equivalent Cl(2)Sr4Ca2 octahedra, edges with three equivalent Cl(1)Sr5Ca octahedra, and edges with four equivalent N(1)Sr4Ca2 octahedra. The corner-sharing octahedral tilt angles range from 12-17°. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to one Sr(3), two equivalent Sr(1), two equivalent Sr(2), and one Ca(1) atom to form distorted ClSr5Ca octahedra that share corners with three equivalent N(1)Sr4Ca2 octahedra, corners with three equivalent N(2)Sr5Ca octahedra, edges with two equivalent Cl(1)Sr5Ca octahedra, edges with three equivalent N(1)Sr4Ca2 octahedra, edges with three equivalent N(2)Sr5Ca octahedra, and edges with four equivalent Cl(2)Sr4Ca2 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. In the second Cl site, Cl(2) is bonded to one Sr(1), one Sr(2), two equivalent Sr(3), and two equivalent Ca(1) atoms to form distorted ClSr4Ca2 octahedra that share corners with three equivalent N(1)Sr4Ca2 octahedra, corners with three equivalent N(2)Sr5Ca octahedra, edges with two equivalent Cl(2)Sr4Ca2 octahedra, edges with three equivalent N(1)Sr4Ca2 octahedra, edges with three equivalent N(2)Sr5Ca octahedra, and edges with four equivalent Cl(1)Sr5Ca octahedra. The corner-sharing octahedral tilt angles range from 12-17°. is represented by the CIF file [CIF]
data_Sr3Ca(NCl)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.368
_cell_length_b   7.368
_cell_length_c   6.673
_cell_angle_alpha   81.343
_cell_angle_beta   81.343
_cell_angle_gamma   30.299
_symmetry_Int_Tables_number   1
_cell_volume   180.518
_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  0.850  0.850  0.381  1.0
  Sr  Sr1  1  0.157  0.157  0.615  1.0
  Sr  Sr2  1  0.654  0.654  0.115  1.0
  Ca  Ca3  1  0.338  0.338  0.890  1.0
  N  N4  1  0.754  0.754  0.755  1.0
  N  N5  1  0.252  0.252  0.243  1.0
  Cl  Cl6  1  0.500  0.500  0.508  1.0
  Cl  Cl7  1  0.996  0.996  0.993  1.0
[/CIF]
.