The material structure described by KNb2PO8 crystallizes in the trigonal R3 space group. K(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 4-38°. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(3), one O(7), and two equivalent O(8) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 4-39°. P(1) is bonded to one O(3), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-41°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one K(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a linear geometry to one Nb(1) and one Nb(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one Nb(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one K(1), one Nb(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one K(1), one Nb(2), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_KNb2PO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.522
_cell_length_b   8.522
_cell_length_c   8.522
_cell_angle_alpha   104.131
_cell_angle_beta   104.131
_cell_angle_gamma   104.131
_symmetry_Int_Tables_number   1
_cell_volume   550.891
_cell_formula_units_Z   3
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
  K  K0  1  0.404  0.091  0.689  1.0
  K  K1  1  0.091  0.689  0.404  1.0
  K  K2  1  0.689  0.404  0.091  1.0
  Nb  Nb3  1  0.647  0.841  0.964  1.0
  Nb  Nb4  1  0.964  0.647  0.841  1.0
  Nb  Nb5  1  0.033  0.158  0.350  1.0
  Nb  Nb6  1  0.841  0.964  0.647  1.0
  Nb  Nb7  1  0.350  0.033  0.158  1.0
  Nb  Nb8  1  0.158  0.350  0.033  1.0
  P  P9  1  0.276  0.500  0.724  1.0
  P  P10  1  0.724  0.276  0.500  1.0
  P  P11  1  0.500  0.724  0.276  1.0
  O  O12  1  0.026  0.501  0.976  1.0
  O  O13  1  0.153  0.847  0.000  1.0
  O  O14  1  0.292  0.416  0.868  1.0
  O  O15  1  0.794  0.685  0.937  1.0
  O  O16  1  0.000  0.153  0.847  1.0
  O  O17  1  0.133  0.583  0.708  1.0
  O  O18  1  0.447  0.642  0.766  1.0
  O  O19  1  0.236  0.358  0.554  1.0
  O  O20  1  0.685  0.937  0.794  1.0
  O  O21  1  0.708  0.133  0.583  1.0
  O  O22  1  0.766  0.447  0.642  1.0
  O  O23  1  0.937  0.794  0.685  1.0
  O  O24  1  0.976  0.026  0.501  1.0
  O  O25  1  0.207  0.063  0.317  1.0
  O  O26  1  0.554  0.236  0.358  1.0
  O  O27  1  0.868  0.292  0.416  1.0
  O  O28  1  0.063  0.317  0.207  1.0
  O  O29  1  0.642  0.766  0.447  1.0
  O  O30  1  0.358  0.554  0.236  1.0
  O  O31  1  0.416  0.868  0.292  1.0
  O  O32  1  0.317  0.207  0.063  1.0
  O  O33  1  0.583  0.708  0.133  1.0
  O  O34  1  0.847  0.000  0.153  1.0
  O  O35  1  0.501  0.976  0.026  1.0
[/CIF]
.
The material structure described by KNb2PO8 crystallizes in the trigonal R3 space group. K(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 4-38°. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(3), one O(7), and two equivalent O(8) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 4-39°. P(1) is bonded to one O(3), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-41°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one K(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a linear geometry to one Nb(1) and one Nb(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one Nb(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one K(1), one Nb(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Nb(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one K(1), one Nb(2), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_KNb2PO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.522
_cell_length_b   8.522
_cell_length_c   8.522
_cell_angle_alpha   104.131
_cell_angle_beta   104.131
_cell_angle_gamma   104.131
_symmetry_Int_Tables_number   1
_cell_volume   550.891
_cell_formula_units_Z   3
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
  K  K0  1  0.404  0.091  0.689  1.0
  K  K1  1  0.091  0.689  0.404  1.0
  K  K2  1  0.689  0.404  0.091  1.0
  Nb  Nb3  1  0.647  0.841  0.964  1.0
  Nb  Nb4  1  0.964  0.647  0.841  1.0
  Nb  Nb5  1  0.033  0.158  0.350  1.0
  Nb  Nb6  1  0.841  0.964  0.647  1.0
  Nb  Nb7  1  0.350  0.033  0.158  1.0
  Nb  Nb8  1  0.158  0.350  0.033  1.0
  P  P9  1  0.276  0.500  0.724  1.0
  P  P10  1  0.724  0.276  0.500  1.0
  P  P11  1  0.500  0.724  0.276  1.0
  O  O12  1  0.026  0.501  0.976  1.0
  O  O13  1  0.153  0.847  0.000  1.0
  O  O14  1  0.292  0.416  0.868  1.0
  O  O15  1  0.794  0.685  0.937  1.0
  O  O16  1  0.000  0.153  0.847  1.0
  O  O17  1  0.133  0.583  0.708  1.0
  O  O18  1  0.447  0.642  0.766  1.0
  O  O19  1  0.236  0.358  0.554  1.0
  O  O20  1  0.685  0.937  0.794  1.0
  O  O21  1  0.708  0.133  0.583  1.0
  O  O22  1  0.766  0.447  0.642  1.0
  O  O23  1  0.937  0.794  0.685  1.0
  O  O24  1  0.976  0.026  0.501  1.0
  O  O25  1  0.207  0.063  0.317  1.0
  O  O26  1  0.554  0.236  0.358  1.0
  O  O27  1  0.868  0.292  0.416  1.0
  O  O28  1  0.063  0.317  0.207  1.0
  O  O29  1  0.642  0.766  0.447  1.0
  O  O30  1  0.358  0.554  0.236  1.0
  O  O31  1  0.416  0.868  0.292  1.0
  O  O32  1  0.317  0.207  0.063  1.0
  O  O33  1  0.583  0.708  0.133  1.0
  O  O34  1  0.847  0.000  0.153  1.0
  O  O35  1  0.501  0.976  0.026  1.0
[/CIF]
.