The structure described by NbCu(PO4)2 crystallizes in the monoclinic P2_1/m space group. Nb(1) is bonded to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form NbO6 pentagonal pyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. Cu(1) is bonded in a 6-coordinate geometry to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with three equivalent Nb(1)O6 pentagonal pyramids. In the second P site, P(2) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 pentagonal pyramid and  an edgeedge with one Nb(1)O6 pentagonal pyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Nb(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(1) and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Nb(1), one Cu(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(1), one Cu(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cu(1) and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbCu(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.207
_cell_length_b   5.121
_cell_length_c   9.952
_cell_angle_alpha   88.816
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   316.316
_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
  Nb  Nb0  1  0.750  0.470  0.776  1.0
  Nb  Nb1  1  0.250  0.530  0.224  1.0
  Cu  Cu2  1  0.250  0.930  0.723  1.0
  Cu  Cu3  1  0.750  0.070  0.277  1.0
  P  P4  1  0.250  0.444  0.900  1.0
  P  P5  1  0.750  0.896  0.597  1.0
  P  P6  1  0.250  0.104  0.403  1.0
  P  P7  1  0.750  0.556  0.100  1.0
  O  O8  1  0.750  0.656  0.949  1.0
  O  O9  1  0.250  0.739  0.895  1.0
  O  O10  1  0.045  0.322  0.833  1.0
  O  O11  1  0.455  0.322  0.833  1.0
  O  O12  1  0.939  0.741  0.672  1.0
  O  O13  1  0.561  0.741  0.672  1.0
  O  O14  1  0.750  0.185  0.643  1.0
  O  O15  1  0.250  0.129  0.551  1.0
  O  O16  1  0.750  0.871  0.449  1.0
  O  O17  1  0.250  0.815  0.357  1.0
  O  O18  1  0.061  0.259  0.328  1.0
  O  O19  1  0.439  0.259  0.328  1.0
  O  O20  1  0.545  0.678  0.167  1.0
  O  O21  1  0.955  0.678  0.167  1.0
  O  O22  1  0.750  0.261  0.105  1.0
  O  O23  1  0.250  0.344  0.051  1.0
[/CIF]
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The structure described by NbCu(PO4)2 crystallizes in the monoclinic P2_1/m space group. Nb(1) is bonded to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form NbO6 pentagonal pyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. Cu(1) is bonded in a 6-coordinate geometry to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with three equivalent Nb(1)O6 pentagonal pyramids. In the second P site, P(2) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 pentagonal pyramid and  an edgeedge with one Nb(1)O6 pentagonal pyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Nb(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(1) and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Nb(1), one Cu(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(1), one Cu(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cu(1) and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbCu(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.207
_cell_length_b   5.121
_cell_length_c   9.952
_cell_angle_alpha   88.816
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   316.316
_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
  Nb  Nb0  1  0.750  0.470  0.776  1.0
  Nb  Nb1  1  0.250  0.530  0.224  1.0
  Cu  Cu2  1  0.250  0.930  0.723  1.0
  Cu  Cu3  1  0.750  0.070  0.277  1.0
  P  P4  1  0.250  0.444  0.900  1.0
  P  P5  1  0.750  0.896  0.597  1.0
  P  P6  1  0.250  0.104  0.403  1.0
  P  P7  1  0.750  0.556  0.100  1.0
  O  O8  1  0.750  0.656  0.949  1.0
  O  O9  1  0.250  0.739  0.895  1.0
  O  O10  1  0.045  0.322  0.833  1.0
  O  O11  1  0.455  0.322  0.833  1.0
  O  O12  1  0.939  0.741  0.672  1.0
  O  O13  1  0.561  0.741  0.672  1.0
  O  O14  1  0.750  0.185  0.643  1.0
  O  O15  1  0.250  0.129  0.551  1.0
  O  O16  1  0.750  0.871  0.449  1.0
  O  O17  1  0.250  0.815  0.357  1.0
  O  O18  1  0.061  0.259  0.328  1.0
  O  O19  1  0.439  0.259  0.328  1.0
  O  O20  1  0.545  0.678  0.167  1.0
  O  O21  1  0.955  0.678  0.167  1.0
  O  O22  1  0.750  0.261  0.105  1.0
  O  O23  1  0.250  0.344  0.051  1.0
[/CIF]
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