data_KSr5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.02
_cell_length_b   8.02
_cell_length_c   8.02
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KSr5
_chemical_formula_sum   'K1 Sr5'
_cell_volume   365.07
_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
  K  K0  1  0.0  0.0  0.0  1.0
  Sr  Sr1  1  0.84  0.84  0.84  1.0
  Sr  Sr2  1  0.09  0.09  0.09  1.0
  Sr  Sr3  1  0.26  0.09  0.26  1.0
  Sr  Sr4  1  0.26  0.26  0.09  1.0
  Sr  Sr5  1  0.09  0.26  0.26  1.0

data_KSr5
_symmetry_space_group_name_H-M   R3m
_cell_length_a   8.02
_cell_length_b   8.02
_cell_length_c   19.65
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   KSr5
_chemical_formula_sum   'K3 Sr15'
_cell_volume   1095.21
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  K  K0  3  0.0  0.0  0.0  1.0
  Sr  Sr1  9  0.12  0.06  0.8  1.0
  Sr  Sr2  3  0.0  0.0  0.16  1.0
  Sr  Sr3  3  0.0  0.0  0.91  1.0

K Sr Sr Sr Sr Sr
Sr2K(Sr)3 is Zincblende, Sphalerite structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three Sr clusters and three Sr2K clusters. In each Sr cluster, Sr(3) is bonded in a 2-coordinate geometry to two equivalent Sr(3) atoms. Both Sr(3)-Sr(3) bond lengths are 1.39 Å. In each Sr2K cluster, K(1) is bonded in a linear geometry to one Sr(1) and one Sr(2) atom. The K(1)-Sr(1) bond length is 3.22 Å. The K(1)-Sr(2) bond length is 1.69 Å. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a single-bond geometry to one K(1) atom. In the second Sr site, Sr(2) is bonded in a single-bond geometry to one K(1) atom.