The material structure described by K9(NbAs3)2 crystallizes in the monoclinic Pc space group. There are nine inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(3), one As(4), and one As(6) atom. In the second K site, K(2) is bonded in a 4-coordinate geometry to one As(1), one As(2), one As(3), and one As(5) atom. In the third K site, K(3) is bonded in a 5-coordinate geometry to one As(2), one As(3), one As(6), and two equivalent As(1) atoms. In the fourth K site, K(4) is bonded in a 5-coordinate geometry to one As(2), one As(4), one As(5), and two equivalent As(3) atoms. In the fifth K site, K(5) is bonded in a 3-coordinate geometry to one As(2), one As(3), and one As(6) atom. In the sixth K site, K(6) is bonded in a 5-coordinate geometry to one As(1), one As(3), one As(4), one As(5), and one As(6) atom. In the seventh K site, K(7) is bonded in a 4-coordinate geometry to one As(2), one As(4), one As(5), and one As(6) atom. In the eighth K site, K(8) is bonded in a 4-coordinate geometry to one As(3), one As(5), one As(6), and two equivalent As(4) atoms. In the ninth K site, K(9) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(5), and two equivalent As(6) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one As(1), one As(3), one As(4), and one As(5) atom to form edge-sharing NbAs4 tetrahedra. In the second Nb site, Nb(2) is bonded to one As(1), one As(2), one As(4), and one As(6) atom to form edge-sharing NbAs4 tetrahedra. There are six inequivalent As sites. In the first As site, As(1) is bonded in a 6-coordinate geometry to one K(1), one K(2), one K(6), one K(9), two equivalent K(3), one Nb(1), and one Nb(2) atom. In the second As site, As(2) is bonded in a 8-coordinate geometry to one K(1), one K(2), one K(3), one K(4), one K(5), one K(7), one K(9), and one Nb(2) atom. In the third As site, As(3) is bonded in a 9-coordinate geometry to one K(1), one K(2), one K(3), one K(5), one K(6), one K(8), two equivalent K(4), and one Nb(1) atom. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to one K(1), one K(4), one K(6), one K(7), two equivalent K(8), one Nb(1), and one Nb(2) atom. In the fifth As site, As(5) is bonded in a 7-coordinate geometry to one K(2), one K(4), one K(6), one K(7), one K(8), one K(9), and one Nb(1) atom. In the sixth As site, As(6) is bonded in a 9-coordinate geometry to one K(1), one K(3), one K(5), one K(6), one K(7), one K(8), two equivalent K(9), and one Nb(2) atom. is represented by the CIF file [CIF]
data_K9(NbAs3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.342
_cell_length_b   9.468
_cell_length_c   12.843
_cell_angle_alpha   83.695
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1129.106
_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
  K  K0  1  0.339  0.586  0.166  1.0
  K  K1  1  0.421  0.932  0.587  1.0
  K  K2  1  0.441  0.624  0.893  1.0
  K  K3  1  0.468  0.182  0.300  1.0
  K  K4  1  0.532  0.182  0.800  1.0
  K  K5  1  0.559  0.624  0.393  1.0
  K  K6  1  0.579  0.932  0.087  1.0
  K  K7  1  0.661  0.586  0.666  1.0
  K  K8  1  0.804  0.014  0.594  1.0
  K  K9  1  0.834  0.407  0.336  1.0
  K  K10  1  0.924  0.070  0.905  1.0
  K  K11  1  0.944  0.396  0.609  1.0
  K  K12  1  0.930  0.803  0.218  1.0
  K  K13  1  0.070  0.803  0.718  1.0
  K  K14  1  0.056  0.396  0.109  1.0
  K  K15  1  0.076  0.070  0.405  1.0
  K  K16  1  0.166  0.407  0.836  1.0
  K  K17  1  0.196  0.014  0.094  1.0
  Nb  Nb18  1  0.325  0.343  0.554  1.0
  Nb  Nb19  1  0.675  0.343  0.054  1.0
  Nb  Nb20  1  0.829  0.657  0.946  1.0
  Nb  Nb21  1  0.171  0.657  0.446  1.0
  As  As22  1  0.306  0.590  0.621  1.0
  As  As23  1  0.298  0.844  0.325  1.0
  As  As24  1  0.414  0.283  0.033  1.0
  As  As25  1  0.586  0.283  0.533  1.0
  As  As26  1  0.702  0.844  0.825  1.0
  As  As27  1  0.694  0.590  0.121  1.0
  As  As28  1  0.806  0.411  0.879  1.0
  As  As29  1  0.812  0.155  0.166  1.0
  As  As30  1  0.915  0.722  0.477  1.0
  As  As31  1  0.085  0.722  0.977  1.0
  As  As32  1  0.188  0.155  0.666  1.0
  As  As33  1  0.194  0.411  0.379  1.0
[/CIF]
.
The material structure described by K9(NbAs3)2 crystallizes in the monoclinic Pc space group. There are nine inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(3), one As(4), and one As(6) atom. In the second K site, K(2) is bonded in a 4-coordinate geometry to one As(1), one As(2), one As(3), and one As(5) atom. In the third K site, K(3) is bonded in a 5-coordinate geometry to one As(2), one As(3), one As(6), and two equivalent As(1) atoms. In the fourth K site, K(4) is bonded in a 5-coordinate geometry to one As(2), one As(4), one As(5), and two equivalent As(3) atoms. In the fifth K site, K(5) is bonded in a 3-coordinate geometry to one As(2), one As(3), and one As(6) atom. In the sixth K site, K(6) is bonded in a 5-coordinate geometry to one As(1), one As(3), one As(4), one As(5), and one As(6) atom. In the seventh K site, K(7) is bonded in a 4-coordinate geometry to one As(2), one As(4), one As(5), and one As(6) atom. In the eighth K site, K(8) is bonded in a 4-coordinate geometry to one As(3), one As(5), one As(6), and two equivalent As(4) atoms. In the ninth K site, K(9) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(5), and two equivalent As(6) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one As(1), one As(3), one As(4), and one As(5) atom to form edge-sharing NbAs4 tetrahedra. In the second Nb site, Nb(2) is bonded to one As(1), one As(2), one As(4), and one As(6) atom to form edge-sharing NbAs4 tetrahedra. There are six inequivalent As sites. In the first As site, As(1) is bonded in a 6-coordinate geometry to one K(1), one K(2), one K(6), one K(9), two equivalent K(3), one Nb(1), and one Nb(2) atom. In the second As site, As(2) is bonded in a 8-coordinate geometry to one K(1), one K(2), one K(3), one K(4), one K(5), one K(7), one K(9), and one Nb(2) atom. In the third As site, As(3) is bonded in a 9-coordinate geometry to one K(1), one K(2), one K(3), one K(5), one K(6), one K(8), two equivalent K(4), and one Nb(1) atom. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to one K(1), one K(4), one K(6), one K(7), two equivalent K(8), one Nb(1), and one Nb(2) atom. In the fifth As site, As(5) is bonded in a 7-coordinate geometry to one K(2), one K(4), one K(6), one K(7), one K(8), one K(9), and one Nb(1) atom. In the sixth As site, As(6) is bonded in a 9-coordinate geometry to one K(1), one K(3), one K(5), one K(6), one K(7), one K(8), two equivalent K(9), and one Nb(2) atom. is represented by the CIF file [CIF]
data_K9(NbAs3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.342
_cell_length_b   9.468
_cell_length_c   12.843
_cell_angle_alpha   83.695
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1129.106
_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
  K  K0  1  0.339  0.586  0.166  1.0
  K  K1  1  0.421  0.932  0.587  1.0
  K  K2  1  0.441  0.624  0.893  1.0
  K  K3  1  0.468  0.182  0.300  1.0
  K  K4  1  0.532  0.182  0.800  1.0
  K  K5  1  0.559  0.624  0.393  1.0
  K  K6  1  0.579  0.932  0.087  1.0
  K  K7  1  0.661  0.586  0.666  1.0
  K  K8  1  0.804  0.014  0.594  1.0
  K  K9  1  0.834  0.407  0.336  1.0
  K  K10  1  0.924  0.070  0.905  1.0
  K  K11  1  0.944  0.396  0.609  1.0
  K  K12  1  0.930  0.803  0.218  1.0
  K  K13  1  0.070  0.803  0.718  1.0
  K  K14  1  0.056  0.396  0.109  1.0
  K  K15  1  0.076  0.070  0.405  1.0
  K  K16  1  0.166  0.407  0.836  1.0
  K  K17  1  0.196  0.014  0.094  1.0
  Nb  Nb18  1  0.325  0.343  0.554  1.0
  Nb  Nb19  1  0.675  0.343  0.054  1.0
  Nb  Nb20  1  0.829  0.657  0.946  1.0
  Nb  Nb21  1  0.171  0.657  0.446  1.0
  As  As22  1  0.306  0.590  0.621  1.0
  As  As23  1  0.298  0.844  0.325  1.0
  As  As24  1  0.414  0.283  0.033  1.0
  As  As25  1  0.586  0.283  0.533  1.0
  As  As26  1  0.702  0.844  0.825  1.0
  As  As27  1  0.694  0.590  0.121  1.0
  As  As28  1  0.806  0.411  0.879  1.0
  As  As29  1  0.812  0.155  0.166  1.0
  As  As30  1  0.915  0.722  0.477  1.0
  As  As31  1  0.085  0.722  0.977  1.0
  As  As32  1  0.188  0.155  0.666  1.0
  As  As33  1  0.194  0.411  0.379  1.0
[/CIF]
.