data_Li2MgAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.67
_cell_length_b   4.67
_cell_length_c   4.67
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li2MgAs
_chemical_formula_sum   'Li2 Mg1 As1'
_cell_volume   71.93
_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
  Li  Li1  1  0.65  0.65  0.65  1.0
  Li  Li2  1  0.0  0.0  0.0  1.0
  Mg  Mg3  1  0.3  0.3  0.3  1.0
  As  As0  1  0.95  0.95  0.95  1.0

data_Li2MgAs
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.67
_cell_length_b   4.67
_cell_length_c   11.43
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Li2MgAs
_chemical_formula_sum   'Li6 Mg3 As3'
_cell_volume   215.8
_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
  Li  Li0  3  0.0  0.0  -0.0  1.0
  Li  Li1  3  0.0  0.0  0.35  1.0
  Mg  Mg2  3  0.0  0.0  0.7  1.0
  As  As3  3  0.0  0.0  0.05  1.0

Li Li Mg As
Li Li Mg As 0 2 o o + 0 2 o + o 0 2 + o o 0 1 o + + 0 1 + o + 0 1 + + o 0 3 - o o 0 3 o - o 0 3 o o - 1 3 - - - 1 2 o o - 1 2 o - o 1 2 - o o 2 3 - - o 2 3 - o - 2 3 o - - 
Li2MgAs crystallizes in the trigonal R3m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted hexagonal planar geometry to three equivalent Mg(1) and three equivalent As(1) atoms. All Li(1)-Mg(1) bond lengths are 2.70 Å. All Li(1)-As(1) bond lengths are 2.72 Å. In the second Li site, Li(2) is bonded in a single-bond geometry to four equivalent Mg(1) and one As(1) atom. There are three shorter (2.72 Å) and one longer (3.44 Å) Li(2)-Mg(1) bond length. The Li(2)-As(1) bond length is 0.56 Å. Mg(1) is bonded in a 10-coordinate geometry to three equivalent Li(1), four equivalent Li(2), and three equivalent As(1) atoms. All Mg(1)-As(1) bond lengths are 2.70 Å. As(1) is bonded in a single-bond geometry to one Li(2), three equivalent Li(1), and three equivalent Mg(1) atoms.