The material described by MgAs crystallizes in the trigonal R32 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent As(1) and four equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Mg(1) atoms to form distorted corner-sharing AsMg6 pentagonal pyramids. In the second As site, As(2) is bonded in a 7-coordinate geometry to six equivalent Mg(1) and one As(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.094
_cell_length_b   5.094
_cell_length_c   5.094
_cell_angle_alpha   86.473
_cell_angle_beta   86.473
_cell_angle_gamma   86.473
_symmetry_Int_Tables_number   1
_cell_volume   131.478
_cell_formula_units_Z   3
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  0.134  0.866  0.500  1.0
  Mg  Mg1  1  0.500  0.134  0.866  1.0
  Mg  Mg2  1  0.866  0.500  0.134  1.0
  As  As3  1  0.000  0.000  0.000  1.0
  As  As4  1  0.364  0.364  0.364  1.0
  As  As5  1  0.636  0.636  0.636  1.0
[/CIF]
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The material described by MgAs crystallizes in the trigonal R32 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent As(1) and four equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Mg(1) atoms to form distorted corner-sharing AsMg6 pentagonal pyramids. In the second As site, As(2) is bonded in a 7-coordinate geometry to six equivalent Mg(1) and one As(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.094
_cell_length_b   5.094
_cell_length_c   5.094
_cell_angle_alpha   86.473
_cell_angle_beta   86.473
_cell_angle_gamma   86.473
_symmetry_Int_Tables_number   1
_cell_volume   131.478
_cell_formula_units_Z   3
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  0.134  0.866  0.500  1.0
  Mg  Mg1  1  0.500  0.134  0.866  1.0
  Mg  Mg2  1  0.866  0.500  0.134  1.0
  As  As3  1  0.000  0.000  0.000  1.0
  As  As4  1  0.364  0.364  0.364  1.0
  As  As5  1  0.636  0.636  0.636  1.0
[/CIF]
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