data_Ca2MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.53
_cell_length_b   6.25
_cell_length_c   6.25
_cell_angle_alpha   38.78
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca2MgSi
_chemical_formula_sum   'Ca2 Mg1 Si1'
_cell_volume   110.88
_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  0.0  0.0  0.53  1.0
  Ca  Ca1  1  0.26  0.0  0.01  1.0
  Mg  Mg2  1  0.0  0.0  0.2  1.0
  Si  Si3  1  0.26  0.0  0.77  1.0

data_Ca2MgSi
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.15
_cell_length_b   4.53
_cell_length_c   6.25
_cell_angle_alpha   90.0
_cell_angle_beta   109.39
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca2MgSi
_chemical_formula_sum   'Ca2 Mg1 Si1'
_cell_volume   110.88
_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  0.47  0.0  0.47  1.0
  Ca  Ca1  1  0.99  0.26  0.99  1.0
  Mg  Mg2  1  0.8  0.0  0.8  1.0
  Si  Si3  1  0.23  0.26  0.23  1.0

Ca Ca Mg Si
Ca Ca Mg Si 0 2 o o o 0 3 o o o 1 2 o o o 1 3 o o - 