The compound described by Mg4TiN4 crystallizes in the triclinic P-1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form distorted MgN4 trigonal pyramids that share  a cornercorner with one Mg(3)N5 square pyramid, corners with three equivalent Mg(4)N5 square pyramids, corners with four equivalent Ti(1)N4 tetrahedra,  an edgeedge with one Mg(4)N5 square pyramid, and edges with two equivalent Mg(3)N5 square pyramids. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent N(2) and two equivalent N(3) atoms. In the third Mg site, Mg(3) is bonded to one N(3), two equivalent N(1), and two equivalent N(4) atoms to form MgN5 square pyramids that share corners with three equivalent Mg(4)N5 square pyramids, corners with three equivalent Ti(1)N4 tetrahedra,  a cornercorner with one Mg(1)N4 trigonal pyramid, edges with two equivalent Mg(3)N5 square pyramids, edges with three equivalent Mg(4)N5 square pyramids,  an edgeedge with one Ti(1)N4 tetrahedra, and edges with two equivalent Mg(1)N4 trigonal pyramids. In the fourth Mg site, Mg(4) is bonded to one N(3), two equivalent N(1), and two equivalent N(4) atoms to form MgN5 square pyramids that share corners with three equivalent Mg(3)N5 square pyramids,  a cornercorner with one Ti(1)N4 tetrahedra, corners with three equivalent Mg(1)N4 trigonal pyramids, edges with two equivalent Mg(4)N5 square pyramids, edges with three equivalent Mg(3)N5 square pyramids, edges with two equivalent Ti(1)N4 tetrahedra, and  an edgeedge with one Mg(1)N4 trigonal pyramid. Ti(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form TiN4 tetrahedra that share  a cornercorner with one Mg(4)N5 square pyramid, corners with three equivalent Mg(3)N5 square pyramids, corners with four equivalent Mg(1)N4 trigonal pyramids,  an edgeedge with one Mg(3)N5 square pyramid, and edges with two equivalent Mg(4)N5 square pyramids. There are four inequivalent N sites. In the first N site, N(1) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), and one Ti(1) atom to form NMg5Ti octahedra that share corners with two equivalent N(3)Mg5Ti octahedra, corners with two equivalent N(4)Mg5Ti octahedra, corners with two equivalent N(2)Mg3Ti tetrahedra, edges with two equivalent N(1)Mg5Ti octahedra, edges with two equivalent N(3)Mg5Ti octahedra, and edges with four equivalent N(4)Mg5Ti octahedra. The corner-sharing octahedral tilt angles range from 9-17°. In the second N site, N(2) is bonded to one Mg(1), two equivalent Mg(2), and one Ti(1) atom to form NMg3Ti tetrahedra that share corners with two equivalent N(1)Mg5Ti octahedra, corners with two equivalent N(4)Mg5Ti octahedra, corners with six equivalent N(3)Mg5Ti octahedra, and  an edgeedge with one N(2)Mg3Ti tetrahedra. The corner-sharing octahedral tilt angles range from 56-65°. In the third N site, N(3) is bonded to one Mg(1), one Mg(3), one Mg(4), two equivalent Mg(2), and one Ti(1) atom to form NMg5Ti octahedra that share corners with two equivalent N(1)Mg5Ti octahedra, corners with six equivalent N(2)Mg3Ti tetrahedra,  an edgeedge with one N(3)Mg5Ti octahedra, edges with two equivalent N(1)Mg5Ti octahedra, and edges with three equivalent N(4)Mg5Ti octahedra. The corner-sharing octahedral tilt angles range from 9-10°. In the fourth N site, N(4) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), and one Ti(1) atom to form NMg5Ti octahedra that share corners with two equivalent N(1)Mg5Ti octahedra, corners with two equivalent N(2)Mg3Ti tetrahedra, edges with two equivalent N(4)Mg5Ti octahedra, edges with three equivalent N(3)Mg5Ti octahedra, and edges with four equivalent N(1)Mg5Ti octahedra. The corner-sharing octahedral tilt angles range from 12-17°. is represented by the CIF card [CIF]
data_Mg4TiN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.465
_cell_length_b   5.483
_cell_length_c   8.288
_cell_angle_alpha   70.649
_cell_angle_beta   82.730
_cell_angle_gamma   68.930
_symmetry_Int_Tables_number   1
_cell_volume   218.600
_cell_formula_units_Z   2
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  0.727  0.620  0.204  1.0
  Mg  Mg1  1  0.273  0.380  0.796  1.0
  Mg  Mg2  1  0.755  0.243  0.997  1.0
  Mg  Mg3  1  0.245  0.757  0.003  1.0
  Mg  Mg4  1  0.737  0.480  0.574  1.0
  Mg  Mg5  1  0.263  0.520  0.426  1.0
  Mg  Mg6  1  0.258  0.934  0.587  1.0
  Mg  Mg7  1  0.742  0.066  0.413  1.0
  Ti  Ti8  1  0.722  0.837  0.770  1.0
  Ti  Ti9  1  0.278  0.163  0.230  1.0
  N  N10  1  0.993  0.700  0.608  1.0
  N  N11  1  0.007  0.300  0.392  1.0
  N  N12  1  0.841  0.846  0.973  1.0
  N  N13  1  0.159  0.154  0.027  1.0
  N  N14  1  0.506  0.611  0.804  1.0
  N  N15  1  0.494  0.389  0.196  1.0
  N  N16  1  0.490  0.812  0.379  1.0
  N  N17  1  0.510  0.188  0.621  1.0
[/CIF]
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The compound described by Mg4TiN4 crystallizes in the triclinic P-1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form distorted MgN4 trigonal pyramids that share  a cornercorner with one Mg(3)N5 square pyramid, corners with three equivalent Mg(4)N5 square pyramids, corners with four equivalent Ti(1)N4 tetrahedra,  an edgeedge with one Mg(4)N5 square pyramid, and edges with two equivalent Mg(3)N5 square pyramids. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent N(2) and two equivalent N(3) atoms. In the third Mg site, Mg(3) is bonded to one N(3), two equivalent N(1), and two equivalent N(4) atoms to form MgN5 square pyramids that share corners with three equivalent Mg(4)N5 square pyramids, corners with three equivalent Ti(1)N4 tetrahedra,  a cornercorner with one Mg(1)N4 trigonal pyramid, edges with two equivalent Mg(3)N5 square pyramids, edges with three equivalent Mg(4)N5 square pyramids,  an edgeedge with one Ti(1)N4 tetrahedra, and edges with two equivalent Mg(1)N4 trigonal pyramids. In the fourth Mg site, Mg(4) is bonded to one N(3), two equivalent N(1), and two equivalent N(4) atoms to form MgN5 square pyramids that share corners with three equivalent Mg(3)N5 square pyramids,  a cornercorner with one Ti(1)N4 tetrahedra, corners with three equivalent Mg(1)N4 trigonal pyramids, edges with two equivalent Mg(4)N5 square pyramids, edges with three equivalent Mg(3)N5 square pyramids, edges with two equivalent Ti(1)N4 tetrahedra, and  an edgeedge with one Mg(1)N4 trigonal pyramid. Ti(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form TiN4 tetrahedra that share  a cornercorner with one Mg(4)N5 square pyramid, corners with three equivalent Mg(3)N5 square pyramids, corners with four equivalent Mg(1)N4 trigonal pyramids,  an edgeedge with one Mg(3)N5 square pyramid, and edges with two equivalent Mg(4)N5 square pyramids. There are four inequivalent N sites. In the first N site, N(1) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), and one Ti(1) atom to form NMg5Ti octahedra that share corners with two equivalent N(3)Mg5Ti octahedra, corners with two equivalent N(4)Mg5Ti octahedra, corners with two equivalent N(2)Mg3Ti tetrahedra, edges with two equivalent N(1)Mg5Ti octahedra, edges with two equivalent N(3)Mg5Ti octahedra, and edges with four equivalent N(4)Mg5Ti octahedra. The corner-sharing octahedral tilt angles range from 9-17°. In the second N site, N(2) is bonded to one Mg(1), two equivalent Mg(2), and one Ti(1) atom to form NMg3Ti tetrahedra that share corners with two equivalent N(1)Mg5Ti octahedra, corners with two equivalent N(4)Mg5Ti octahedra, corners with six equivalent N(3)Mg5Ti octahedra, and  an edgeedge with one N(2)Mg3Ti tetrahedra. The corner-sharing octahedral tilt angles range from 56-65°. In the third N site, N(3) is bonded to one Mg(1), one Mg(3), one Mg(4), two equivalent Mg(2), and one Ti(1) atom to form NMg5Ti octahedra that share corners with two equivalent N(1)Mg5Ti octahedra, corners with six equivalent N(2)Mg3Ti tetrahedra,  an edgeedge with one N(3)Mg5Ti octahedra, edges with two equivalent N(1)Mg5Ti octahedra, and edges with three equivalent N(4)Mg5Ti octahedra. The corner-sharing octahedral tilt angles range from 9-10°. In the fourth N site, N(4) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), and one Ti(1) atom to form NMg5Ti octahedra that share corners with two equivalent N(1)Mg5Ti octahedra, corners with two equivalent N(2)Mg3Ti tetrahedra, edges with two equivalent N(4)Mg5Ti octahedra, edges with three equivalent N(3)Mg5Ti octahedra, and edges with four equivalent N(1)Mg5Ti octahedra. The corner-sharing octahedral tilt angles range from 12-17°. is represented by the CIF card [CIF]
data_Mg4TiN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.465
_cell_length_b   5.483
_cell_length_c   8.288
_cell_angle_alpha   70.649
_cell_angle_beta   82.730
_cell_angle_gamma   68.930
_symmetry_Int_Tables_number   1
_cell_volume   218.600
_cell_formula_units_Z   2
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  0.727  0.620  0.204  1.0
  Mg  Mg1  1  0.273  0.380  0.796  1.0
  Mg  Mg2  1  0.755  0.243  0.997  1.0
  Mg  Mg3  1  0.245  0.757  0.003  1.0
  Mg  Mg4  1  0.737  0.480  0.574  1.0
  Mg  Mg5  1  0.263  0.520  0.426  1.0
  Mg  Mg6  1  0.258  0.934  0.587  1.0
  Mg  Mg7  1  0.742  0.066  0.413  1.0
  Ti  Ti8  1  0.722  0.837  0.770  1.0
  Ti  Ti9  1  0.278  0.163  0.230  1.0
  N  N10  1  0.993  0.700  0.608  1.0
  N  N11  1  0.007  0.300  0.392  1.0
  N  N12  1  0.841  0.846  0.973  1.0
  N  N13  1  0.159  0.154  0.027  1.0
  N  N14  1  0.506  0.611  0.804  1.0
  N  N15  1  0.494  0.389  0.196  1.0
  N  N16  1  0.490  0.812  0.379  1.0
  N  N17  1  0.510  0.188  0.621  1.0
[/CIF]
.