The material described by Nb2P4O15 crystallizes in the triclinic P1 space group. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(13), one O(16), one O(19), one O(25), and one O(30) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the second Nb site, Nb(2) is bonded to one O(10), one O(15), one O(2), one O(20), one O(22), and one O(5) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra, and  a cornercorner with one P(6)O4 tetrahedra. In the third Nb site, Nb(3) is bonded to one O(12), one O(17), one O(26), one O(29), one O(3), and one O(6) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the fourth Nb site, Nb(4) is bonded to one O(18), one O(23), one O(28), one O(4), one O(7), and one O(9) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-28°. In the second P site, P(2) is bonded to one O(10), one O(11), one O(8), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 28-35°. In the third P site, P(3) is bonded to one O(11), one O(12), one O(13), and one O(14) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 24-37°. In the fourth P site, P(4) is bonded to one O(14), one O(15), one O(16), and one O(17) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 5-24°. In the fifth P site, P(5) is bonded to one O(18), one O(19), one O(20), and one O(21) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra, and  a cornercorner with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 23-34°. In the sixth P site, P(6) is bonded to one O(21), one O(22), one O(23), and one O(24) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra,  a cornercorner with one P(5)O4 tetrahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-34°. In the seventh P site, P(7) is bonded to one O(24), one O(25), one O(26), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one P(6)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 23-37°. In the eighth P site, P(8) is bonded to one O(27), one O(28), one O(29), and one O(30) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-26°. There are thirty inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Nb(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Nb(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Nb(3) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Nb(4) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(2) and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Nb(3) and one P(1) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Nb(2) and one P(2) atom. In the eleventh O site, O(11) is bonded in a linear geometry to one P(2) and one P(3) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Nb(3) and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one P(3) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one P(3) and one P(4) atom. In the fifteenth O site, O(15) is bonded in a linear geometry to one Nb(2) and one P(4) atom. In the sixteenth O site, O(16) is bonded in a linear geometry to one Nb(1) and one P(4) atom. In the seventeenth O site, O(17) is bonded in a bent 150 degrees geometry to one Nb(3) and one P(4) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(5) atom. In the nineteenth O site, O(19) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(5) atom. In the twentieth O site, O(20) is bonded in a bent 150 degrees geometry to one Nb(2) and one P(5) atom. In the twenty-first O site, O(21) is bonded in a bent 150 degrees geometry to one P(5) and one P(6) atom. In the twenty-second O site, O(22) is bonded in a distorted bent 150 degrees geometry to one Nb(2) and one P(6) atom. In the twenty-third O site, O(23) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(6) atom. In the twenty-fourth O site, O(24) is bonded in a linear geometry to one P(6) and one P(7) atom. In the twenty-fifth O site, O(25) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(7) atom. In the twenty-sixth O site, O(26) is bonded in a distorted bent 150 degrees geometry to one Nb(3) and one P(7) atom. In the twenty-seventh O site, O(27) is bonded in a bent 150 degrees geometry to one P(7) and one P(8) atom. In the twenty-eighth O site, O(28) is bonded in a linear geometry to one Nb(4) and one P(8) atom. In the twenty-ninth O site, O(29) is bonded in a linear geometry to one Nb(3) and one P(8) atom. In the thirtieth O site, O(30) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(8) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2P4O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.790
_cell_length_b   8.538
_cell_length_c   11.181
_cell_angle_alpha   74.340
_cell_angle_beta   89.827
_cell_angle_gamma   89.936
_symmetry_Int_Tables_number   1
_cell_volume   624.146
_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  0.784  0.690  0.115  1.0
  Nb  Nb1  1  0.808  0.685  0.608  1.0
  Nb  Nb2  1  0.281  0.272  0.905  1.0
  Nb  Nb3  1  0.306  0.280  0.409  1.0
  P  P4  1  0.606  0.295  0.663  1.0
  P  P5  1  0.927  0.068  0.630  1.0
  P  P6  1  0.156  0.896  0.875  1.0
  P  P7  1  0.482  0.661  0.865  1.0
  P  P8  1  0.104  0.668  0.355  1.0
  P  P9  1  0.425  0.897  0.389  1.0
  P  P10  1  0.656  0.066  0.143  1.0
  P  P11  1  0.980  0.300  0.157  1.0
  O  O12  1  0.614  0.646  0.235  1.0
  O  O13  1  0.020  0.647  0.696  1.0
  O  O14  1  0.102  0.316  0.791  1.0
  O  O15  1  0.508  0.320  0.310  1.0
  O  O16  1  0.719  0.453  0.614  1.0
  O  O17  1  0.516  0.280  0.790  1.0
  O  O18  1  0.456  0.265  0.570  1.0
  O  O19  1  0.755  0.145  0.693  1.0
  O  O20  1  0.039  0.193  0.537  1.0
  O  O21  1  0.831  0.934  0.583  1.0
  O  O22  1  0.059  0.988  0.746  1.0
  O  O23  1  0.250  0.024  0.930  1.0
  O  O24  1  0.020  0.778  0.957  1.0
  O  O25  1  0.334  0.812  0.821  1.0
  O  O26  1  0.612  0.673  0.752  1.0
  O  O27  1  0.596  0.692  0.974  1.0
  O  O28  1  0.363  0.505  0.904  1.0
  O  O29  1  0.217  0.511  0.409  1.0
  O  O30  1  0.026  0.681  0.224  1.0
  O  O31  1  0.943  0.698  0.442  1.0
  O  O32  1  0.251  0.819  0.329  1.0
  O  O33  1  0.539  0.773  0.482  1.0
  O  O34  1  0.331  0.032  0.435  1.0
  O  O35  1  0.552  0.976  0.269  1.0
  O  O36  1  0.754  0.938  0.090  1.0
  O  O37  1  0.525  0.184  0.058  1.0
  O  O38  1  0.830  0.150  0.199  1.0
  O  O39  1  0.099  0.291  0.273  1.0
  O  O40  1  0.104  0.266  0.053  1.0
  O  O41  1  0.863  0.457  0.113  1.0
[/CIF]
.
The material described by Nb2P4O15 crystallizes in the triclinic P1 space group. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(13), one O(16), one O(19), one O(25), and one O(30) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the second Nb site, Nb(2) is bonded to one O(10), one O(15), one O(2), one O(20), one O(22), and one O(5) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra, and  a cornercorner with one P(6)O4 tetrahedra. In the third Nb site, Nb(3) is bonded to one O(12), one O(17), one O(26), one O(29), one O(3), and one O(6) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the fourth Nb site, Nb(4) is bonded to one O(18), one O(23), one O(28), one O(4), one O(7), and one O(9) atom to form distorted NbO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-28°. In the second P site, P(2) is bonded to one O(10), one O(11), one O(8), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 28-35°. In the third P site, P(3) is bonded to one O(11), one O(12), one O(13), and one O(14) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 24-37°. In the fourth P site, P(4) is bonded to one O(14), one O(15), one O(16), and one O(17) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 5-24°. In the fifth P site, P(5) is bonded to one O(18), one O(19), one O(20), and one O(21) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra, and  a cornercorner with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 23-34°. In the sixth P site, P(6) is bonded to one O(21), one O(22), one O(23), and one O(24) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(2)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra,  a cornercorner with one P(5)O4 tetrahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-34°. In the seventh P site, P(7) is bonded to one O(24), one O(25), one O(26), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one P(6)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 23-37°. In the eighth P site, P(8) is bonded to one O(27), one O(28), one O(29), and one O(30) atom to form PO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6 octahedra,  a cornercorner with one Nb(4)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-26°. There are thirty inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Nb(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Nb(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Nb(3) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Nb(4) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(2) and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Nb(3) and one P(1) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Nb(2) and one P(2) atom. In the eleventh O site, O(11) is bonded in a linear geometry to one P(2) and one P(3) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Nb(3) and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one P(3) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one P(3) and one P(4) atom. In the fifteenth O site, O(15) is bonded in a linear geometry to one Nb(2) and one P(4) atom. In the sixteenth O site, O(16) is bonded in a linear geometry to one Nb(1) and one P(4) atom. In the seventeenth O site, O(17) is bonded in a bent 150 degrees geometry to one Nb(3) and one P(4) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(5) atom. In the nineteenth O site, O(19) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(5) atom. In the twentieth O site, O(20) is bonded in a bent 150 degrees geometry to one Nb(2) and one P(5) atom. In the twenty-first O site, O(21) is bonded in a bent 150 degrees geometry to one P(5) and one P(6) atom. In the twenty-second O site, O(22) is bonded in a distorted bent 150 degrees geometry to one Nb(2) and one P(6) atom. In the twenty-third O site, O(23) is bonded in a bent 150 degrees geometry to one Nb(4) and one P(6) atom. In the twenty-fourth O site, O(24) is bonded in a linear geometry to one P(6) and one P(7) atom. In the twenty-fifth O site, O(25) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(7) atom. In the twenty-sixth O site, O(26) is bonded in a distorted bent 150 degrees geometry to one Nb(3) and one P(7) atom. In the twenty-seventh O site, O(27) is bonded in a bent 150 degrees geometry to one P(7) and one P(8) atom. In the twenty-eighth O site, O(28) is bonded in a linear geometry to one Nb(4) and one P(8) atom. In the twenty-ninth O site, O(29) is bonded in a linear geometry to one Nb(3) and one P(8) atom. In the thirtieth O site, O(30) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(8) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2P4O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.790
_cell_length_b   8.538
_cell_length_c   11.181
_cell_angle_alpha   74.340
_cell_angle_beta   89.827
_cell_angle_gamma   89.936
_symmetry_Int_Tables_number   1
_cell_volume   624.146
_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  0.784  0.690  0.115  1.0
  Nb  Nb1  1  0.808  0.685  0.608  1.0
  Nb  Nb2  1  0.281  0.272  0.905  1.0
  Nb  Nb3  1  0.306  0.280  0.409  1.0
  P  P4  1  0.606  0.295  0.663  1.0
  P  P5  1  0.927  0.068  0.630  1.0
  P  P6  1  0.156  0.896  0.875  1.0
  P  P7  1  0.482  0.661  0.865  1.0
  P  P8  1  0.104  0.668  0.355  1.0
  P  P9  1  0.425  0.897  0.389  1.0
  P  P10  1  0.656  0.066  0.143  1.0
  P  P11  1  0.980  0.300  0.157  1.0
  O  O12  1  0.614  0.646  0.235  1.0
  O  O13  1  0.020  0.647  0.696  1.0
  O  O14  1  0.102  0.316  0.791  1.0
  O  O15  1  0.508  0.320  0.310  1.0
  O  O16  1  0.719  0.453  0.614  1.0
  O  O17  1  0.516  0.280  0.790  1.0
  O  O18  1  0.456  0.265  0.570  1.0
  O  O19  1  0.755  0.145  0.693  1.0
  O  O20  1  0.039  0.193  0.537  1.0
  O  O21  1  0.831  0.934  0.583  1.0
  O  O22  1  0.059  0.988  0.746  1.0
  O  O23  1  0.250  0.024  0.930  1.0
  O  O24  1  0.020  0.778  0.957  1.0
  O  O25  1  0.334  0.812  0.821  1.0
  O  O26  1  0.612  0.673  0.752  1.0
  O  O27  1  0.596  0.692  0.974  1.0
  O  O28  1  0.363  0.505  0.904  1.0
  O  O29  1  0.217  0.511  0.409  1.0
  O  O30  1  0.026  0.681  0.224  1.0
  O  O31  1  0.943  0.698  0.442  1.0
  O  O32  1  0.251  0.819  0.329  1.0
  O  O33  1  0.539  0.773  0.482  1.0
  O  O34  1  0.331  0.032  0.435  1.0
  O  O35  1  0.552  0.976  0.269  1.0
  O  O36  1  0.754  0.938  0.090  1.0
  O  O37  1  0.525  0.184  0.058  1.0
  O  O38  1  0.830  0.150  0.199  1.0
  O  O39  1  0.099  0.291  0.273  1.0
  O  O40  1  0.104  0.266  0.053  1.0
  O  O41  1  0.863  0.457  0.113  1.0
[/CIF]
.