The material structure described by Mg4SiN4 crystallizes in the orthorhombic Pnna space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one N(2) and three equivalent N(1) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to four equivalent N(2) atoms. In the third Mg site, Mg(3) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted MgN4 trigonal pyramids that share edges with two equivalent Si(1)N4 tetrahedra. Si(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form SiN4 tetrahedra that share edges with two equivalent Mg(3)N4 trigonal pyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 5-coordinate geometry to one Mg(3), three equivalent Mg(1), and one Si(1) atom. In the second N site, N(2) is bonded in a 5-coordinate geometry to one Mg(1), one Mg(3), two equivalent Mg(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_Mg4SiN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.223
_cell_length_b   10.275
_cell_length_c   8.375
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   449.485
_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  0.149  0.371  0.608  1.0
  Mg  Mg1  1  0.351  0.629  0.608  1.0
  Mg  Mg2  1  0.149  0.129  0.892  1.0
  Mg  Mg3  1  0.351  0.871  0.892  1.0
  Mg  Mg4  1  0.851  0.629  0.392  1.0
  Mg  Mg5  1  0.649  0.371  0.392  1.0
  Mg  Mg6  1  0.851  0.871  0.108  1.0
  Mg  Mg7  1  0.649  0.129  0.108  1.0
  Mg  Mg8  1  0.750  0.500  0.054  1.0
  Mg  Mg9  1  0.750  0.000  0.446  1.0
  Mg  Mg10  1  0.250  0.500  0.946  1.0
  Mg  Mg11  1  0.250  0.000  0.554  1.0
  Mg  Mg12  1  0.692  0.250  0.750  1.0
  Mg  Mg13  1  0.808  0.750  0.750  1.0
  Mg  Mg14  1  0.308  0.750  0.250  1.0
  Mg  Mg15  1  0.192  0.250  0.250  1.0
  Si  Si16  1  0.750  0.500  0.734  1.0
  Si  Si17  1  0.750  0.000  0.766  1.0
  Si  Si18  1  0.250  0.500  0.266  1.0
  Si  Si19  1  0.250  0.000  0.234  1.0
  N  N20  1  0.536  0.400  0.627  1.0
  N  N21  1  0.964  0.600  0.627  1.0
  N  N22  1  0.536  0.100  0.873  1.0
  N  N23  1  0.964  0.900  0.873  1.0
  N  N24  1  0.464  0.600  0.373  1.0
  N  N25  1  0.036  0.400  0.373  1.0
  N  N26  1  0.464  0.900  0.127  1.0
  N  N27  1  0.036  0.100  0.127  1.0
  N  N28  1  0.946  0.107  0.652  1.0
  N  N29  1  0.554  0.893  0.652  1.0
  N  N30  1  0.946  0.393  0.848  1.0
  N  N31  1  0.554  0.607  0.848  1.0
  N  N32  1  0.054  0.893  0.348  1.0
  N  N33  1  0.446  0.107  0.348  1.0
  N  N34  1  0.054  0.607  0.152  1.0
  N  N35  1  0.446  0.393  0.152  1.0
[/CIF]
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The material structure described by Mg4SiN4 crystallizes in the orthorhombic Pnna space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one N(2) and three equivalent N(1) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to four equivalent N(2) atoms. In the third Mg site, Mg(3) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted MgN4 trigonal pyramids that share edges with two equivalent Si(1)N4 tetrahedra. Si(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form SiN4 tetrahedra that share edges with two equivalent Mg(3)N4 trigonal pyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 5-coordinate geometry to one Mg(3), three equivalent Mg(1), and one Si(1) atom. In the second N site, N(2) is bonded in a 5-coordinate geometry to one Mg(1), one Mg(3), two equivalent Mg(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_Mg4SiN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.223
_cell_length_b   10.275
_cell_length_c   8.375
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   449.485
_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  0.149  0.371  0.608  1.0
  Mg  Mg1  1  0.351  0.629  0.608  1.0
  Mg  Mg2  1  0.149  0.129  0.892  1.0
  Mg  Mg3  1  0.351  0.871  0.892  1.0
  Mg  Mg4  1  0.851  0.629  0.392  1.0
  Mg  Mg5  1  0.649  0.371  0.392  1.0
  Mg  Mg6  1  0.851  0.871  0.108  1.0
  Mg  Mg7  1  0.649  0.129  0.108  1.0
  Mg  Mg8  1  0.750  0.500  0.054  1.0
  Mg  Mg9  1  0.750  0.000  0.446  1.0
  Mg  Mg10  1  0.250  0.500  0.946  1.0
  Mg  Mg11  1  0.250  0.000  0.554  1.0
  Mg  Mg12  1  0.692  0.250  0.750  1.0
  Mg  Mg13  1  0.808  0.750  0.750  1.0
  Mg  Mg14  1  0.308  0.750  0.250  1.0
  Mg  Mg15  1  0.192  0.250  0.250  1.0
  Si  Si16  1  0.750  0.500  0.734  1.0
  Si  Si17  1  0.750  0.000  0.766  1.0
  Si  Si18  1  0.250  0.500  0.266  1.0
  Si  Si19  1  0.250  0.000  0.234  1.0
  N  N20  1  0.536  0.400  0.627  1.0
  N  N21  1  0.964  0.600  0.627  1.0
  N  N22  1  0.536  0.100  0.873  1.0
  N  N23  1  0.964  0.900  0.873  1.0
  N  N24  1  0.464  0.600  0.373  1.0
  N  N25  1  0.036  0.400  0.373  1.0
  N  N26  1  0.464  0.900  0.127  1.0
  N  N27  1  0.036  0.100  0.127  1.0
  N  N28  1  0.946  0.107  0.652  1.0
  N  N29  1  0.554  0.893  0.652  1.0
  N  N30  1  0.946  0.393  0.848  1.0
  N  N31  1  0.554  0.607  0.848  1.0
  N  N32  1  0.054  0.893  0.348  1.0
  N  N33  1  0.446  0.107  0.348  1.0
  N  N34  1  0.054  0.607  0.152  1.0
  N  N35  1  0.446  0.393  0.152  1.0
[/CIF]
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