The crystal structure described by Mg3(PO4)2 crystallizes in the triclinic P-1 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(2), one O(4), and one O(9) atom. In the second Mg site, Mg(2) is bonded to one O(11), one O(13), one O(15), one O(16), one O(2), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra, and  an edgeedge with one Mg(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 70°. In the third Mg site, Mg(3) is bonded to one O(15), one O(3), one O(6), one O(7), and two equivalent O(12) atoms to form distorted MgO6 octahedra that share  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra, and  an edgeedge with one Mg(3)O6 octahedra. The corner-sharing octahedral tilt angles are 80°. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(16), one O(2), one O(8), and one O(9) atom to form MgO5 trigonal bipyramids that share  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. In the fifth Mg site, Mg(5) is bonded to one O(13), one O(14), one O(6), one O(8), and two equivalent O(5) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  a cornercorner with one Mg(4)O5 trigonal bipyramid,  an edgeedge with one Mg(5)O6 octahedra, and  an edgeedge with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 70-80°. In the sixth Mg site, Mg(6) is bonded to one O(10), one O(3), one O(4), and two equivalent O(1) atoms to form distorted MgO5 square pyramids that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  a cornercorner with one Mg(4)O5 trigonal bipyramid, and  an edgeedge with one Mg(6)O5 square pyramid. The corner-sharing octahedral tilt angles are 58°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(11), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(5)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, and corners with two equivalent Mg(6)O5 square pyramids. The corner-sharing octahedral tilt angles range from 34-57°. In the second P site, P(2) is bonded to one O(12), one O(14), one O(2), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid, and  a cornercorner with one Mg(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-61°. In the third P site, P(3) is bonded to one O(16), one O(3), one O(5), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Mg(5)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid, and corners with two equivalent Mg(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 45-69°. In the fourth P site, P(4) is bonded to one O(10), one O(13), one O(15), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid, corners with two equivalent Mg(4)O5 trigonal bipyramids, and  an edgeedge with one Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-50°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Mg(6), and one P(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(2), one Mg(4), and one P(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mg(3), one Mg(6), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(6), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Mg(5) and one P(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(3), one Mg(5), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(2), one Mg(3), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Mg(4), one Mg(5), and one P(4) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(4), and one P(3) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(4), one Mg(6), and one P(4) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to two equivalent Mg(3) and one P(2) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(5), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a 2-coordinate geometry to one Mg(5) and one P(2) atom. In the fifteenth O site, O(15) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(3), and one P(4) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Mg(2), one Mg(4), and one P(3) atom. is represented by the CIF file [CIF]
data_Mg3(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.612
_cell_length_b   9.093
_cell_length_c   9.419
_cell_angle_alpha   115.934
_cell_angle_beta   91.395
_cell_angle_gamma   114.413
_symmetry_Int_Tables_number   1
_cell_volume   584.733
_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  0.078  0.302  0.874  1.0
  Mg  Mg1  1  0.594  0.523  0.263  1.0
  Mg  Mg2  1  0.516  0.891  0.822  1.0
  Mg  Mg3  1  0.484  0.109  0.178  1.0
  Mg  Mg4  1  0.983  0.707  0.444  1.0
  Mg  Mg5  1  0.599  0.193  0.674  1.0
  Mg  Mg6  1  0.903  0.819  0.839  1.0
  Mg  Mg7  1  0.401  0.807  0.326  1.0
  Mg  Mg8  1  0.406  0.477  0.737  1.0
  Mg  Mg9  1  0.097  0.181  0.161  1.0
  Mg  Mg10  1  0.017  0.293  0.556  1.0
  Mg  Mg11  1  0.922  0.698  0.126  1.0
  P  P12  1  0.329  0.179  0.907  1.0
  P  P13  1  0.178  0.690  0.947  1.0
  P  P14  1  0.671  0.821  0.093  1.0
  P  P15  1  0.764  0.928  0.599  1.0
  P  P16  1  0.730  0.433  0.549  1.0
  P  P17  1  0.270  0.567  0.451  1.0
  P  P18  1  0.236  0.072  0.401  1.0
  P  P19  1  0.822  0.310  0.053  1.0
  O  O20  1  0.132  0.060  0.904  1.0
  O  O21  1  0.157  0.502  0.801  1.0
  O  O22  1  0.246  0.096  0.247  1.0
  O  O23  1  0.843  0.498  0.199  1.0
  O  O24  1  0.003  0.699  0.930  1.0
  O  O25  1  0.600  0.944  0.553  1.0
  O  O26  1  0.409  0.073  0.783  1.0
  O  O27  1  0.434  0.268  0.084  1.0
  O  O28  1  0.212  0.708  0.457  1.0
  O  O29  1  0.934  0.111  0.645  1.0
  O  O30  1  0.107  0.373  0.390  1.0
  O  O31  1  0.566  0.732  0.916  1.0
  O  O32  1  0.324  0.331  0.873  1.0
  O  O33  1  0.671  0.140  0.047  1.0
  O  O34  1  0.676  0.669  0.127  1.0
  O  O35  1  0.620  0.445  0.680  1.0
  O  O36  1  0.205  0.679  0.105  1.0
  O  O37  1  0.377  0.629  0.619  1.0
  O  O38  1  0.591  0.927  0.217  1.0
  O  O39  1  0.772  0.764  0.457  1.0
  O  O40  1  0.997  0.301  0.070  1.0
  O  O41  1  0.400  0.056  0.447  1.0
  O  O42  1  0.788  0.292  0.543  1.0
  O  O43  1  0.380  0.555  0.320  1.0
  O  O44  1  0.228  0.236  0.543  1.0
  O  O45  1  0.623  0.371  0.381  1.0
  O  O46  1  0.329  0.860  0.953  1.0
  O  O47  1  0.754  0.904  0.753  1.0
  O  O48  1  0.795  0.321  0.895  1.0
  O  O49  1  0.868  0.940  0.096  1.0
  O  O50  1  0.893  0.627  0.610  1.0
  O  O51  1  0.066  0.889  0.355  1.0
[/CIF]
.
The crystal structure described by Mg3(PO4)2 crystallizes in the triclinic P-1 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(2), one O(4), and one O(9) atom. In the second Mg site, Mg(2) is bonded to one O(11), one O(13), one O(15), one O(16), one O(2), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra, and  an edgeedge with one Mg(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 70°. In the third Mg site, Mg(3) is bonded to one O(15), one O(3), one O(6), one O(7), and two equivalent O(12) atoms to form distorted MgO6 octahedra that share  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra, and  an edgeedge with one Mg(3)O6 octahedra. The corner-sharing octahedral tilt angles are 80°. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(16), one O(2), one O(8), and one O(9) atom to form MgO5 trigonal bipyramids that share  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. In the fifth Mg site, Mg(5) is bonded to one O(13), one O(14), one O(6), one O(8), and two equivalent O(5) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  a cornercorner with one Mg(4)O5 trigonal bipyramid,  an edgeedge with one Mg(5)O6 octahedra, and  an edgeedge with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 70-80°. In the sixth Mg site, Mg(6) is bonded to one O(10), one O(3), one O(4), and two equivalent O(1) atoms to form distorted MgO5 square pyramids that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  a cornercorner with one Mg(4)O5 trigonal bipyramid, and  an edgeedge with one Mg(6)O5 square pyramid. The corner-sharing octahedral tilt angles are 58°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(11), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(5)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, and corners with two equivalent Mg(6)O5 square pyramids. The corner-sharing octahedral tilt angles range from 34-57°. In the second P site, P(2) is bonded to one O(12), one O(14), one O(2), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid, and  a cornercorner with one Mg(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-61°. In the third P site, P(3) is bonded to one O(16), one O(3), one O(5), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Mg(5)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid, and corners with two equivalent Mg(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 45-69°. In the fourth P site, P(4) is bonded to one O(10), one O(13), one O(15), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra,  a cornercorner with one Mg(6)O5 square pyramid, corners with two equivalent Mg(4)O5 trigonal bipyramids, and  an edgeedge with one Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-50°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Mg(6), and one P(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(2), one Mg(4), and one P(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mg(3), one Mg(6), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(6), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Mg(5) and one P(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(3), one Mg(5), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(2), one Mg(3), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Mg(4), one Mg(5), and one P(4) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(4), and one P(3) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(4), one Mg(6), and one P(4) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to two equivalent Mg(3) and one P(2) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(5), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a 2-coordinate geometry to one Mg(5) and one P(2) atom. In the fifteenth O site, O(15) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(3), and one P(4) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Mg(2), one Mg(4), and one P(3) atom. is represented by the CIF file [CIF]
data_Mg3(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.612
_cell_length_b   9.093
_cell_length_c   9.419
_cell_angle_alpha   115.934
_cell_angle_beta   91.395
_cell_angle_gamma   114.413
_symmetry_Int_Tables_number   1
_cell_volume   584.733
_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  0.078  0.302  0.874  1.0
  Mg  Mg1  1  0.594  0.523  0.263  1.0
  Mg  Mg2  1  0.516  0.891  0.822  1.0
  Mg  Mg3  1  0.484  0.109  0.178  1.0
  Mg  Mg4  1  0.983  0.707  0.444  1.0
  Mg  Mg5  1  0.599  0.193  0.674  1.0
  Mg  Mg6  1  0.903  0.819  0.839  1.0
  Mg  Mg7  1  0.401  0.807  0.326  1.0
  Mg  Mg8  1  0.406  0.477  0.737  1.0
  Mg  Mg9  1  0.097  0.181  0.161  1.0
  Mg  Mg10  1  0.017  0.293  0.556  1.0
  Mg  Mg11  1  0.922  0.698  0.126  1.0
  P  P12  1  0.329  0.179  0.907  1.0
  P  P13  1  0.178  0.690  0.947  1.0
  P  P14  1  0.671  0.821  0.093  1.0
  P  P15  1  0.764  0.928  0.599  1.0
  P  P16  1  0.730  0.433  0.549  1.0
  P  P17  1  0.270  0.567  0.451  1.0
  P  P18  1  0.236  0.072  0.401  1.0
  P  P19  1  0.822  0.310  0.053  1.0
  O  O20  1  0.132  0.060  0.904  1.0
  O  O21  1  0.157  0.502  0.801  1.0
  O  O22  1  0.246  0.096  0.247  1.0
  O  O23  1  0.843  0.498  0.199  1.0
  O  O24  1  0.003  0.699  0.930  1.0
  O  O25  1  0.600  0.944  0.553  1.0
  O  O26  1  0.409  0.073  0.783  1.0
  O  O27  1  0.434  0.268  0.084  1.0
  O  O28  1  0.212  0.708  0.457  1.0
  O  O29  1  0.934  0.111  0.645  1.0
  O  O30  1  0.107  0.373  0.390  1.0
  O  O31  1  0.566  0.732  0.916  1.0
  O  O32  1  0.324  0.331  0.873  1.0
  O  O33  1  0.671  0.140  0.047  1.0
  O  O34  1  0.676  0.669  0.127  1.0
  O  O35  1  0.620  0.445  0.680  1.0
  O  O36  1  0.205  0.679  0.105  1.0
  O  O37  1  0.377  0.629  0.619  1.0
  O  O38  1  0.591  0.927  0.217  1.0
  O  O39  1  0.772  0.764  0.457  1.0
  O  O40  1  0.997  0.301  0.070  1.0
  O  O41  1  0.400  0.056  0.447  1.0
  O  O42  1  0.788  0.292  0.543  1.0
  O  O43  1  0.380  0.555  0.320  1.0
  O  O44  1  0.228  0.236  0.543  1.0
  O  O45  1  0.623  0.371  0.381  1.0
  O  O46  1  0.329  0.860  0.953  1.0
  O  O47  1  0.754  0.904  0.753  1.0
  O  O48  1  0.795  0.321  0.895  1.0
  O  O49  1  0.868  0.940  0.096  1.0
  O  O50  1  0.893  0.627  0.610  1.0
  O  O51  1  0.066  0.889  0.355  1.0
[/CIF]
.