The structure described by MgCuP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(7), and two equivalent O(5) atoms. Cu(1) is bonded to one O(2), one O(4), one O(7), and two equivalent O(6) atoms to form distorted CuO5 square pyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one Cu(1)O5 square pyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Cu(1)O5 square pyramids and  a cornercorner with one P(2)O4 tetrahedra. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 square pyramids and  a cornercorner with one P(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) 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(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Cu(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCuP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.206
_cell_length_b   6.316
_cell_length_c   7.017
_cell_angle_alpha   68.320
_cell_angle_beta   79.979
_cell_angle_gamma   80.752
_symmetry_Int_Tables_number   1
_cell_volume   250.274
_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  0.895  0.281  0.161  1.0
  Mg  Mg1  1  0.105  0.719  0.839  1.0
  Cu  Cu2  1  0.679  0.095  0.783  1.0
  Cu  Cu3  1  0.321  0.905  0.217  1.0
  P  P4  1  0.172  0.230  0.749  1.0
  P  P5  1  0.828  0.770  0.251  1.0
  P  P6  1  0.624  0.633  0.695  1.0
  P  P7  1  0.376  0.367  0.305  1.0
  O  O8  1  0.765  0.607  0.482  1.0
  O  O9  1  0.235  0.393  0.518  1.0
  O  O10  1  0.004  0.069  0.756  1.0
  O  O11  1  0.996  0.931  0.244  1.0
  O  O12  1  0.609  0.269  0.351  1.0
  O  O13  1  0.391  0.731  0.649  1.0
  O  O14  1  0.357  0.616  0.153  1.0
  O  O15  1  0.643  0.384  0.847  1.0
  O  O16  1  0.926  0.609  0.133  1.0
  O  O17  1  0.074  0.391  0.867  1.0
  O  O18  1  0.630  0.930  0.163  1.0
  O  O19  1  0.370  0.070  0.837  1.0
  O  O20  1  0.244  0.215  0.249  1.0
  O  O21  1  0.756  0.785  0.751  1.0
[/CIF]
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The structure described by MgCuP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(7), and two equivalent O(5) atoms. Cu(1) is bonded to one O(2), one O(4), one O(7), and two equivalent O(6) atoms to form distorted CuO5 square pyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one Cu(1)O5 square pyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Cu(1)O5 square pyramids and  a cornercorner with one P(2)O4 tetrahedra. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 square pyramids and  a cornercorner with one P(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) 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(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Cu(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCuP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.206
_cell_length_b   6.316
_cell_length_c   7.017
_cell_angle_alpha   68.320
_cell_angle_beta   79.979
_cell_angle_gamma   80.752
_symmetry_Int_Tables_number   1
_cell_volume   250.274
_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  0.895  0.281  0.161  1.0
  Mg  Mg1  1  0.105  0.719  0.839  1.0
  Cu  Cu2  1  0.679  0.095  0.783  1.0
  Cu  Cu3  1  0.321  0.905  0.217  1.0
  P  P4  1  0.172  0.230  0.749  1.0
  P  P5  1  0.828  0.770  0.251  1.0
  P  P6  1  0.624  0.633  0.695  1.0
  P  P7  1  0.376  0.367  0.305  1.0
  O  O8  1  0.765  0.607  0.482  1.0
  O  O9  1  0.235  0.393  0.518  1.0
  O  O10  1  0.004  0.069  0.756  1.0
  O  O11  1  0.996  0.931  0.244  1.0
  O  O12  1  0.609  0.269  0.351  1.0
  O  O13  1  0.391  0.731  0.649  1.0
  O  O14  1  0.357  0.616  0.153  1.0
  O  O15  1  0.643  0.384  0.847  1.0
  O  O16  1  0.926  0.609  0.133  1.0
  O  O17  1  0.074  0.391  0.867  1.0
  O  O18  1  0.630  0.930  0.163  1.0
  O  O19  1  0.370  0.070  0.837  1.0
  O  O20  1  0.244  0.215  0.249  1.0
  O  O21  1  0.756  0.785  0.751  1.0
[/CIF]
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