data_Ca2ZnGe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   5.2
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca2ZnGe
_chemical_formula_sum   'Ca2 Zn1 Ge1'
_cell_volume   99.18
_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
  Ca  Ca0  1  0.84  0.84  0.84  1.0
  Ca  Ca1  1  0.0  0.0  0.0  1.0
  Zn  Zn3  1  0.67  0.67  0.67  1.0
  Ge  Ge2  1  0.51  0.51  0.51  1.0

data_Ca2ZnGe
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   12.73
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Ca2ZnGe
_chemical_formula_sum   'Ca6 Zn3 Ge3'
_cell_volume   297.55
_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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  Ca  Ca1  3  0.0  0.0  0.16  1.0
  Zn  Zn2  3  0.0  0.0  0.33  1.0
  Ge  Ge3  3  0.0  0.0  0.49  1.0

Ca Ca Zn Ge
Ca2ZnGe crystallizes in the trigonal R3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted single-bond geometry to one Ca(2), one Zn(1), and three equivalent Ge(1) atoms. The Ca(1)-Ca(2) bond length is 2.07 Å. The Ca(1)-Zn(1) bond length is 2.07 Å. All Ca(1)-Ge(1) bond lengths are 3.00 Å. In the second Ca site, Ca(2) is bonded to one Ca(1) and three equivalent Zn(1) atoms to form CaCaZn3 trigonal pyramids that share  a cornercorner with one Zn(1)Ca4Ge trigonal bipyramid, corners with six equivalent Ca(2)CaZn3 trigonal pyramids, and edges with three equivalent Ge(1)Ca3Zn trigonal pyramids. All Ca(2)-Zn(1) bond lengths are 3.00 Å. Zn(1) is bonded to one Ca(1), three equivalent Ca(2), and one Ge(1) atom to form distorted ZnCa4Ge trigonal bipyramids that share corners with six equivalent Zn(1)Ca4Ge trigonal bipyramids,  a cornercorner with one Ca(2)CaZn3 trigonal pyramid, and corners with three equivalent Ge(1)Ca3Zn trigonal pyramids. The Zn(1)-Ge(1) bond length is 2.07 Å. Ge(1) is bonded to three equivalent Ca(1) and one Zn(1) atom to form GeCa3Zn trigonal pyramids that share corners with three equivalent Zn(1)Ca4Ge trigonal bipyramids, corners with six equivalent Ge(1)Ca3Zn trigonal pyramids, and edges with three equivalent Ca(2)CaZn3 trigonal pyramids.