data_MgAs2Pt
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.16
_cell_length_b   6.16
_cell_length_c   6.16
_cell_angle_alpha   148.98
_cell_angle_beta   137.91
_cell_angle_gamma   53.19
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgAs2Pt
_chemical_formula_sum   'Mg1 As2 Pt1'
_cell_volume   80.13
_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
  Mg  Mg2  1  0.0  0.0  0.0  1.0
  As  As0  1  0.65  0.0  0.53  1.0
  As  As1  1  0.0  0.21  0.98  1.0
  Pt  Pt3  1  0.0  0.0  0.5  1.0

data_MgAs2Pt
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.29
_cell_length_b   4.42
_cell_length_c   6.16
_cell_angle_alpha   111.04
_cell_angle_beta   105.51
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgAs2Pt
_chemical_formula_sum   'Mg1 As2 Pt1'
_cell_volume   80.13
_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
  Mg  Mg0  1  0.0  0.0  0.0  1.0
  As  As1  1  0.02  0.23  0.23  1.0
  As  As2  1  0.12  0.47  0.12  1.0
  Pt  Pt3  1  0.5  0.5  0.5  1.0

Mg As As Pt
Mg As As Pt 0 2 o o - 1 2 + o o 1 3 + o o 2 3 o o o 
MgPtAs2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted single-bond geometry to one Pt(1), one As(2), and two equivalent As(1) atoms. The Mg(1)-Pt(1) bond length is 3.11 Å. The Mg(1)-As(2) bond length is 1.42 Å. There is one shorter (1.95 Å) and one longer (2.68 Å) Mg(1)-As(1) bond length. Pt(1) is bonded in a 4-coordinate geometry to one Mg(1), one As(1), and two equivalent As(2) atoms. The Pt(1)-As(1) bond length is 2.29 Å. There is one shorter (1.91 Å) and one longer (2.66 Å) Pt(1)-As(2) bond length. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1), one Pt(1), and one As(2) atom. The As(1)-As(2) bond length is 1.54 Å. In the second As site, As(2) is bonded in a distorted single-bond geometry to one Mg(1), two equivalent Pt(1), and one As(1) atom.