The material described by MgTa2N3 is Caswellsilverite-like structured and crystallizes in the hexagonal P6_3/mcm space group. Mg(1) is bonded to six equivalent N(1) atoms to form MgN6 octahedra that share corners with six equivalent Ta(1)N6 pentagonal pyramids, edges with three equivalent Mg(1)N6 octahedra, edges with three equivalent Ta(2)N6 octahedra, and edges with six equivalent Ta(1)N6 pentagonal pyramids. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to six equivalent N(1) atoms to form distorted TaN6 pentagonal pyramids that share corners with two equivalent Ta(2)N6 octahedra, corners with four equivalent Mg(1)N6 octahedra, edges with two equivalent Ta(2)N6 octahedra, edges with four equivalent Mg(1)N6 octahedra, and edges with six equivalent Ta(1)N6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 2-3°. In the second Ta site, Ta(2) is bonded to six equivalent N(1) atoms to form TaN6 octahedra that share corners with six equivalent Ta(1)N6 pentagonal pyramids, edges with six equivalent Mg(1)N6 octahedra, and edges with six equivalent Ta(1)N6 pentagonal pyramids. N(1) is bonded to two equivalent Mg(1), one Ta(2), and three equivalent Ta(1) atoms to form a mixture of edge, corner, and face-sharing NMg2Ta4 octahedra. The corner-sharing octahedral tilt angles range from 0-48°. is represented by the CIF file [CIF]
data_MgTa2N3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.213
_cell_length_b   5.213
_cell_length_c   10.458
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   246.154
_cell_formula_units_Z   4
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  0.333  0.667  0.000  1.0
  Mg  Mg1  1  0.333  0.667  0.500  1.0
  Mg  Mg2  1  0.667  0.333  0.500  1.0
  Mg  Mg3  1  0.667  0.333  0.000  1.0
  Ta  Ta4  1  0.000  0.336  0.250  1.0
  Ta  Ta5  1  0.664  1.000  0.750  1.0
  Ta  Ta6  1  0.336  0.336  0.750  1.0
  Ta  Ta7  1  0.000  0.000  0.500  1.0
  Ta  Ta8  1  0.000  0.000  0.000  1.0
  Ta  Ta9  1  0.664  0.664  0.250  1.0
  Ta  Ta10  1  0.336  0.000  0.250  1.0
  Ta  Ta11  1  1.000  0.664  0.750  1.0
  N  N12  1  0.671  0.671  0.620  1.0
  N  N13  1  0.671  0.671  0.880  1.0
  N  N14  1  0.329  0.329  0.120  1.0
  N  N15  1  0.329  0.329  0.380  1.0
  N  N16  1  0.329  1.000  0.880  1.0
  N  N17  1  0.329  1.000  0.620  1.0
  N  N18  1  0.000  0.671  0.380  1.0
  N  N19  1  0.000  0.671  0.120  1.0
  N  N20  1  0.671  0.000  0.120  1.0
  N  N21  1  0.671  0.000  0.380  1.0
  N  N22  1  1.000  0.329  0.880  1.0
  N  N23  1  1.000  0.329  0.620  1.0
[/CIF]
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The material described by MgTa2N3 is Caswellsilverite-like structured and crystallizes in the hexagonal P6_3/mcm space group. Mg(1) is bonded to six equivalent N(1) atoms to form MgN6 octahedra that share corners with six equivalent Ta(1)N6 pentagonal pyramids, edges with three equivalent Mg(1)N6 octahedra, edges with three equivalent Ta(2)N6 octahedra, and edges with six equivalent Ta(1)N6 pentagonal pyramids. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to six equivalent N(1) atoms to form distorted TaN6 pentagonal pyramids that share corners with two equivalent Ta(2)N6 octahedra, corners with four equivalent Mg(1)N6 octahedra, edges with two equivalent Ta(2)N6 octahedra, edges with four equivalent Mg(1)N6 octahedra, and edges with six equivalent Ta(1)N6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 2-3°. In the second Ta site, Ta(2) is bonded to six equivalent N(1) atoms to form TaN6 octahedra that share corners with six equivalent Ta(1)N6 pentagonal pyramids, edges with six equivalent Mg(1)N6 octahedra, and edges with six equivalent Ta(1)N6 pentagonal pyramids. N(1) is bonded to two equivalent Mg(1), one Ta(2), and three equivalent Ta(1) atoms to form a mixture of edge, corner, and face-sharing NMg2Ta4 octahedra. The corner-sharing octahedral tilt angles range from 0-48°. is represented by the CIF file [CIF]
data_MgTa2N3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.213
_cell_length_b   5.213
_cell_length_c   10.458
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   246.154
_cell_formula_units_Z   4
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  0.333  0.667  0.000  1.0
  Mg  Mg1  1  0.333  0.667  0.500  1.0
  Mg  Mg2  1  0.667  0.333  0.500  1.0
  Mg  Mg3  1  0.667  0.333  0.000  1.0
  Ta  Ta4  1  0.000  0.336  0.250  1.0
  Ta  Ta5  1  0.664  1.000  0.750  1.0
  Ta  Ta6  1  0.336  0.336  0.750  1.0
  Ta  Ta7  1  0.000  0.000  0.500  1.0
  Ta  Ta8  1  0.000  0.000  0.000  1.0
  Ta  Ta9  1  0.664  0.664  0.250  1.0
  Ta  Ta10  1  0.336  0.000  0.250  1.0
  Ta  Ta11  1  1.000  0.664  0.750  1.0
  N  N12  1  0.671  0.671  0.620  1.0
  N  N13  1  0.671  0.671  0.880  1.0
  N  N14  1  0.329  0.329  0.120  1.0
  N  N15  1  0.329  0.329  0.380  1.0
  N  N16  1  0.329  1.000  0.880  1.0
  N  N17  1  0.329  1.000  0.620  1.0
  N  N18  1  0.000  0.671  0.380  1.0
  N  N19  1  0.000  0.671  0.120  1.0
  N  N20  1  0.671  0.000  0.120  1.0
  N  N21  1  0.671  0.000  0.380  1.0
  N  N22  1  1.000  0.329  0.880  1.0
  N  N23  1  1.000  0.329  0.620  1.0
[/CIF]
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