The structure described by MgCu(PO3)4 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra, and edges with two equivalent Cu(1)O6 octahedra. Cu(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form CuO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with four equivalent P(1)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, and corners with two equivalent P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 24-59°. In the second P site, P(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 19-59°. There are six inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to one Cu(1) and one P(1) atom. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cu(1), and one P(1) atom. In the third O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cu(1), and one P(2) atom. In the fourth O site, O(6) is bonded in a bent 150 degrees geometry to one Mg(1) and one P(2) atom. In the fifth O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(2) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCu(PO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.289
_cell_length_b   7.289
_cell_length_c   10.049
_cell_angle_alpha   66.876
_cell_angle_beta   66.876
_cell_angle_gamma   70.161
_symmetry_Int_Tables_number   1
_cell_volume   440.574
_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  0.951  0.049  0.250  1.0
  Mg  Mg1  1  0.049  0.951  0.750  1.0
  Cu  Cu2  1  0.500  0.000  0.500  1.0
  Cu  Cu3  1  0.000  0.500  0.000  1.0
  P  P4  1  0.317  0.293  0.196  1.0
  P  P5  1  0.707  0.683  0.304  1.0
  P  P6  1  0.683  0.707  0.804  1.0
  P  P7  1  0.293  0.317  0.696  1.0
  P  P8  1  0.732  0.253  0.977  1.0
  P  P9  1  0.747  0.268  0.523  1.0
  P  P10  1  0.268  0.747  0.023  1.0
  P  P11  1  0.253  0.732  0.477  1.0
  O  O12  1  0.317  0.531  0.150  1.0
  O  O13  1  0.469  0.683  0.350  1.0
  O  O14  1  0.683  0.469  0.850  1.0
  O  O15  1  0.531  0.317  0.650  1.0
  O  O16  1  0.506  0.211  0.067  1.0
  O  O17  1  0.789  0.494  0.433  1.0
  O  O18  1  0.494  0.789  0.933  1.0
  O  O19  1  0.211  0.506  0.567  1.0
  O  O20  1  0.346  0.190  0.349  1.0
  O  O21  1  0.810  0.654  0.151  1.0
  O  O22  1  0.654  0.810  0.651  1.0
  O  O23  1  0.190  0.346  0.849  1.0
  O  O24  1  0.126  0.277  0.177  1.0
  O  O25  1  0.723  0.874  0.323  1.0
  O  O26  1  0.874  0.723  0.823  1.0
  O  O27  1  0.277  0.126  0.677  1.0
  O  O28  1  0.814  0.284  0.083  1.0
  O  O29  1  0.716  0.186  0.417  1.0
  O  O30  1  0.186  0.716  0.917  1.0
  O  O31  1  0.284  0.814  0.583  1.0
  O  O32  1  0.850  0.092  0.902  1.0
  O  O33  1  0.908  0.150  0.598  1.0
  O  O34  1  0.150  0.908  0.098  1.0
  O  O35  1  0.092  0.850  0.402  1.0
[/CIF]
.
The structure described by MgCu(PO3)4 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra, and edges with two equivalent Cu(1)O6 octahedra. Cu(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form CuO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with four equivalent P(1)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, and corners with two equivalent P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 24-59°. In the second P site, P(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 19-59°. There are six inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to one Cu(1) and one P(1) atom. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cu(1), and one P(1) atom. In the third O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cu(1), and one P(2) atom. In the fourth O site, O(6) is bonded in a bent 150 degrees geometry to one Mg(1) and one P(2) atom. In the fifth O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(2) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCu(PO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.289
_cell_length_b   7.289
_cell_length_c   10.049
_cell_angle_alpha   66.876
_cell_angle_beta   66.876
_cell_angle_gamma   70.161
_symmetry_Int_Tables_number   1
_cell_volume   440.574
_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  0.951  0.049  0.250  1.0
  Mg  Mg1  1  0.049  0.951  0.750  1.0
  Cu  Cu2  1  0.500  0.000  0.500  1.0
  Cu  Cu3  1  0.000  0.500  0.000  1.0
  P  P4  1  0.317  0.293  0.196  1.0
  P  P5  1  0.707  0.683  0.304  1.0
  P  P6  1  0.683  0.707  0.804  1.0
  P  P7  1  0.293  0.317  0.696  1.0
  P  P8  1  0.732  0.253  0.977  1.0
  P  P9  1  0.747  0.268  0.523  1.0
  P  P10  1  0.268  0.747  0.023  1.0
  P  P11  1  0.253  0.732  0.477  1.0
  O  O12  1  0.317  0.531  0.150  1.0
  O  O13  1  0.469  0.683  0.350  1.0
  O  O14  1  0.683  0.469  0.850  1.0
  O  O15  1  0.531  0.317  0.650  1.0
  O  O16  1  0.506  0.211  0.067  1.0
  O  O17  1  0.789  0.494  0.433  1.0
  O  O18  1  0.494  0.789  0.933  1.0
  O  O19  1  0.211  0.506  0.567  1.0
  O  O20  1  0.346  0.190  0.349  1.0
  O  O21  1  0.810  0.654  0.151  1.0
  O  O22  1  0.654  0.810  0.651  1.0
  O  O23  1  0.190  0.346  0.849  1.0
  O  O24  1  0.126  0.277  0.177  1.0
  O  O25  1  0.723  0.874  0.323  1.0
  O  O26  1  0.874  0.723  0.823  1.0
  O  O27  1  0.277  0.126  0.677  1.0
  O  O28  1  0.814  0.284  0.083  1.0
  O  O29  1  0.716  0.186  0.417  1.0
  O  O30  1  0.186  0.716  0.917  1.0
  O  O31  1  0.284  0.814  0.583  1.0
  O  O32  1  0.850  0.092  0.902  1.0
  O  O33  1  0.908  0.150  0.598  1.0
  O  O34  1  0.150  0.908  0.098  1.0
  O  O35  1  0.092  0.850  0.402  1.0
[/CIF]
.