The material described by Ca2TaN3 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to two equivalent N(1), two equivalent N(3), and three equivalent N(2) atoms. In the second Ca site, Ca(2) is bonded to two equivalent N(2), two equivalent N(3), and three equivalent N(1) atoms to form distorted CaN7 pentagonal bipyramids that share corners with four equivalent Ca(2)N7 pentagonal bipyramids,  a cornercorner with one Ta(1)N4 tetrahedra, edges with three equivalent Ca(2)N7 pentagonal bipyramids, and edges with four equivalent Ta(1)N4 tetrahedra. Ta(1) is bonded to one N(1), one N(2), and two equivalent N(3) atoms to form TaN4 tetrahedra that share  a cornercorner with one Ca(2)N7 pentagonal bipyramid, corners with two equivalent Ta(1)N4 tetrahedra, and edges with four equivalent Ca(2)N7 pentagonal bipyramids. There are three inequivalent N sites. In the first N site, N(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Ta(1) atoms. In the second N site, N(1) is bonded in a 6-coordinate geometry to two equivalent Ca(1), three equivalent Ca(2), and one Ta(1) atom. In the third N site, N(2) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Ta(1) atom to form a mixture of distorted corner and edge-sharing NCa5Ta octahedra. The corner-sharing octahedral tilt angles are 19°. is represented by the CIF card [CIF]
data_Ca2TaN3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.270
_cell_length_b   6.270
_cell_length_c   11.676
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   124.795
_symmetry_Int_Tables_number   1
_cell_volume   376.971
_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
  Ca  Ca0  1  0.537  0.463  0.647  1.0
  Ca  Ca1  1  0.463  0.537  0.353  1.0
  Ca  Ca2  1  0.963  0.037  0.147  1.0
  Ca  Ca3  1  0.037  0.963  0.853  1.0
  Ca  Ca4  1  0.872  0.128  0.579  1.0
  Ca  Ca5  1  0.128  0.872  0.421  1.0
  Ca  Ca6  1  0.628  0.372  0.079  1.0
  Ca  Ca7  1  0.372  0.628  0.921  1.0
  Ta  Ta8  1  0.752  0.248  0.841  1.0
  Ta  Ta9  1  0.248  0.752  0.159  1.0
  Ta  Ta10  1  0.748  0.252  0.341  1.0
  Ta  Ta11  1  0.252  0.748  0.659  1.0
  N  N12  1  0.842  0.158  0.980  1.0
  N  N13  1  0.158  0.842  0.020  1.0
  N  N14  1  0.658  0.342  0.480  1.0
  N  N15  1  0.342  0.658  0.520  1.0
  N  N16  1  0.579  0.421  0.863  1.0
  N  N17  1  0.421  0.579  0.137  1.0
  N  N18  1  0.921  0.079  0.363  1.0
  N  N19  1  0.079  0.921  0.637  1.0
  N  N20  1  0.570  0.930  0.750  1.0
  N  N21  1  0.930  0.570  0.250  1.0
  N  N22  1  0.430  0.070  0.250  1.0
  N  N23  1  0.070  0.430  0.750  1.0
[/CIF]
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The material described by Ca2TaN3 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to two equivalent N(1), two equivalent N(3), and three equivalent N(2) atoms. In the second Ca site, Ca(2) is bonded to two equivalent N(2), two equivalent N(3), and three equivalent N(1) atoms to form distorted CaN7 pentagonal bipyramids that share corners with four equivalent Ca(2)N7 pentagonal bipyramids,  a cornercorner with one Ta(1)N4 tetrahedra, edges with three equivalent Ca(2)N7 pentagonal bipyramids, and edges with four equivalent Ta(1)N4 tetrahedra. Ta(1) is bonded to one N(1), one N(2), and two equivalent N(3) atoms to form TaN4 tetrahedra that share  a cornercorner with one Ca(2)N7 pentagonal bipyramid, corners with two equivalent Ta(1)N4 tetrahedra, and edges with four equivalent Ca(2)N7 pentagonal bipyramids. There are three inequivalent N sites. In the first N site, N(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Ta(1) atoms. In the second N site, N(1) is bonded in a 6-coordinate geometry to two equivalent Ca(1), three equivalent Ca(2), and one Ta(1) atom. In the third N site, N(2) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Ta(1) atom to form a mixture of distorted corner and edge-sharing NCa5Ta octahedra. The corner-sharing octahedral tilt angles are 19°. is represented by the CIF card [CIF]
data_Ca2TaN3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.270
_cell_length_b   6.270
_cell_length_c   11.676
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   124.795
_symmetry_Int_Tables_number   1
_cell_volume   376.971
_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
  Ca  Ca0  1  0.537  0.463  0.647  1.0
  Ca  Ca1  1  0.463  0.537  0.353  1.0
  Ca  Ca2  1  0.963  0.037  0.147  1.0
  Ca  Ca3  1  0.037  0.963  0.853  1.0
  Ca  Ca4  1  0.872  0.128  0.579  1.0
  Ca  Ca5  1  0.128  0.872  0.421  1.0
  Ca  Ca6  1  0.628  0.372  0.079  1.0
  Ca  Ca7  1  0.372  0.628  0.921  1.0
  Ta  Ta8  1  0.752  0.248  0.841  1.0
  Ta  Ta9  1  0.248  0.752  0.159  1.0
  Ta  Ta10  1  0.748  0.252  0.341  1.0
  Ta  Ta11  1  0.252  0.748  0.659  1.0
  N  N12  1  0.842  0.158  0.980  1.0
  N  N13  1  0.158  0.842  0.020  1.0
  N  N14  1  0.658  0.342  0.480  1.0
  N  N15  1  0.342  0.658  0.520  1.0
  N  N16  1  0.579  0.421  0.863  1.0
  N  N17  1  0.421  0.579  0.137  1.0
  N  N18  1  0.921  0.079  0.363  1.0
  N  N19  1  0.079  0.921  0.637  1.0
  N  N20  1  0.570  0.930  0.750  1.0
  N  N21  1  0.930  0.570  0.250  1.0
  N  N22  1  0.430  0.070  0.250  1.0
  N  N23  1  0.070  0.430  0.750  1.0
[/CIF]
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