The structure described by Mg3Bi3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one N(1), one N(5), and two equivalent N(3) atoms to form a mixture of corner and edge-sharing MgN4 tetrahedra. In the second Mg site, Mg(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form a mixture of distorted corner and edge-sharing MgN4 tetrahedra. In the third Mg site, Mg(3) is bonded to one N(1), one N(2), one N(4), and one N(5) atom to form a mixture of distorted corner and edge-sharing MgN4 trigonal pyramids. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a water-like geometry to one N(2) and one N(3) atom. In the second Bi site, Bi(2) is bonded in a 3-coordinate geometry to one N(4) and two equivalent N(5) atoms. In the third Bi site, Bi(3) is bonded in a distorted T-shaped geometry to one N(1), one N(2), and one N(4) atom. There are five inequivalent N sites. In the first N site, N(1) is bonded in a distorted see-saw-like geometry to one Mg(1), one Mg(2), one Mg(3), and one Bi(3) atom. In the second N site, N(2) is bonded to one Mg(2), one Mg(3), one Bi(1), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing NMg2Bi2 trigonal pyramids. In the third N site, N(3) is bonded in a distorted T-shaped geometry to two equivalent Mg(1) and one Bi(1) atom. In the fourth N site, N(4) is bonded to one Mg(3), two equivalent Mg(2), one Bi(2), and one Bi(3) atom to form distorted NMg3Bi2 trigonal bipyramids that share corners with two equivalent N(2)Mg2Bi2 trigonal pyramids,  an edgeedge with one N(4)Mg3Bi2 trigonal bipyramid, and  an edgeedge with one N(2)Mg2Bi2 trigonal pyramid. In the fifth N site, N(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), and two equivalent Bi(2) atoms. is represented by the CIF file [CIF]
data_Mg3Bi3N5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.187
_cell_length_b   7.935
_cell_length_c   8.734
_cell_angle_alpha   98.028
_cell_angle_beta   104.048
_cell_angle_gamma   94.386
_symmetry_Int_Tables_number   1
_cell_volume   409.192
_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  0.896  0.312  0.949  1.0
  Mg  Mg1  1  0.104  0.688  0.051  1.0
  Mg  Mg2  1  0.725  0.021  0.587  1.0
  Mg  Mg3  1  0.275  0.979  0.413  1.0
  Mg  Mg4  1  0.126  0.894  0.741  1.0
  Mg  Mg5  1  0.874  0.106  0.259  1.0
  Bi  Bi6  1  0.774  0.513  0.611  1.0
  Bi  Bi7  1  0.226  0.487  0.389  1.0
  Bi  Bi8  1  0.634  0.902  0.883  1.0
  Bi  Bi9  1  0.366  0.098  0.117  1.0
  Bi  Bi10  1  0.720  0.744  0.285  1.0
  Bi  Bi11  1  0.280  0.256  0.715  1.0
  N  N12  1  0.993  0.133  0.777  1.0
  N  N13  1  0.007  0.867  0.223  1.0
  N  N14  1  0.855  0.769  0.556  1.0
  N  N15  1  0.145  0.231  0.444  1.0
  N  N16  1  0.858  0.545  0.856  1.0
  N  N17  1  0.142  0.455  0.144  1.0
  N  N18  1  0.413  0.998  0.661  1.0
  N  N19  1  0.587  0.002  0.339  1.0
  N  N20  1  0.318  0.844  0.959  1.0
  N  N21  1  0.682  0.156  0.041  1.0
[/CIF]
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The structure described by Mg3Bi3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one N(1), one N(5), and two equivalent N(3) atoms to form a mixture of corner and edge-sharing MgN4 tetrahedra. In the second Mg site, Mg(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form a mixture of distorted corner and edge-sharing MgN4 tetrahedra. In the third Mg site, Mg(3) is bonded to one N(1), one N(2), one N(4), and one N(5) atom to form a mixture of distorted corner and edge-sharing MgN4 trigonal pyramids. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a water-like geometry to one N(2) and one N(3) atom. In the second Bi site, Bi(2) is bonded in a 3-coordinate geometry to one N(4) and two equivalent N(5) atoms. In the third Bi site, Bi(3) is bonded in a distorted T-shaped geometry to one N(1), one N(2), and one N(4) atom. There are five inequivalent N sites. In the first N site, N(1) is bonded in a distorted see-saw-like geometry to one Mg(1), one Mg(2), one Mg(3), and one Bi(3) atom. In the second N site, N(2) is bonded to one Mg(2), one Mg(3), one Bi(1), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing NMg2Bi2 trigonal pyramids. In the third N site, N(3) is bonded in a distorted T-shaped geometry to two equivalent Mg(1) and one Bi(1) atom. In the fourth N site, N(4) is bonded to one Mg(3), two equivalent Mg(2), one Bi(2), and one Bi(3) atom to form distorted NMg3Bi2 trigonal bipyramids that share corners with two equivalent N(2)Mg2Bi2 trigonal pyramids,  an edgeedge with one N(4)Mg3Bi2 trigonal bipyramid, and  an edgeedge with one N(2)Mg2Bi2 trigonal pyramid. In the fifth N site, N(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), and two equivalent Bi(2) atoms. is represented by the CIF file [CIF]
data_Mg3Bi3N5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.187
_cell_length_b   7.935
_cell_length_c   8.734
_cell_angle_alpha   98.028
_cell_angle_beta   104.048
_cell_angle_gamma   94.386
_symmetry_Int_Tables_number   1
_cell_volume   409.192
_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  0.896  0.312  0.949  1.0
  Mg  Mg1  1  0.104  0.688  0.051  1.0
  Mg  Mg2  1  0.725  0.021  0.587  1.0
  Mg  Mg3  1  0.275  0.979  0.413  1.0
  Mg  Mg4  1  0.126  0.894  0.741  1.0
  Mg  Mg5  1  0.874  0.106  0.259  1.0
  Bi  Bi6  1  0.774  0.513  0.611  1.0
  Bi  Bi7  1  0.226  0.487  0.389  1.0
  Bi  Bi8  1  0.634  0.902  0.883  1.0
  Bi  Bi9  1  0.366  0.098  0.117  1.0
  Bi  Bi10  1  0.720  0.744  0.285  1.0
  Bi  Bi11  1  0.280  0.256  0.715  1.0
  N  N12  1  0.993  0.133  0.777  1.0
  N  N13  1  0.007  0.867  0.223  1.0
  N  N14  1  0.855  0.769  0.556  1.0
  N  N15  1  0.145  0.231  0.444  1.0
  N  N16  1  0.858  0.545  0.856  1.0
  N  N17  1  0.142  0.455  0.144  1.0
  N  N18  1  0.413  0.998  0.661  1.0
  N  N19  1  0.587  0.002  0.339  1.0
  N  N20  1  0.318  0.844  0.959  1.0
  N  N21  1  0.682  0.156  0.041  1.0
[/CIF]
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