The material structure described by K4P21I crystallizes in the orthorhombic Cmcm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one P(1), one P(6), one P(7), two equivalent P(3), and one I(1) atom. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent P(2), two equivalent P(4), two equivalent P(8), and two equivalent I(1) atoms. There are eight inequivalent P sites. In the first P site, P(5) is bonded in a distorted trigonal non-coplanar geometry to one P(1) and two equivalent P(8) atoms. In the second P site, P(6) is bonded to one K(1), one P(2), and two equivalent P(4) atoms to form PKP3 tetrahedra that share  a cornercorner with one I(1)K6 pentagonal pyramid, corners with two equivalent P(7)KP3 tetrahedra, and corners with two equivalent P(4)KP3 trigonal pyramids. In the third P site, P(7) is bonded to one K(1), one P(2), and two equivalent P(3) atoms to form PKP3 tetrahedra that share  a cornercorner with one I(1)K6 pentagonal pyramid, corners with two equivalent P(6)KP3 tetrahedra, corners with two equivalent P(8)KP3 tetrahedra, and corners with two equivalent P(4)KP3 trigonal pyramids. In the fourth P site, P(8) is bonded to one K(2), one P(3), one P(5), and one P(8) atom to form PKP3 tetrahedra that share corners with two equivalent I(1)K6 pentagonal pyramids,  a cornercorner with one P(7)KP3 tetrahedra, corners with two equivalent P(8)KP3 tetrahedra,  a cornercorner with one P(4)KP3 trigonal pyramid, corners with two equivalent P(2)K2P2 trigonal pyramids, and  an edgeedge with one P(4)KP3 trigonal pyramid. In the fifth P site, P(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(1) and two equivalent P(5) atoms. In the sixth P site, P(2) is bonded to two equivalent K(2), one P(6), and one P(7) atom to form PK2P2 trigonal pyramids that share corners with two equivalent I(1)K6 pentagonal pyramids, corners with four equivalent P(8)KP3 tetrahedra, corners with two equivalent P(2)K2P2 trigonal pyramids, corners with six equivalent P(4)KP3 trigonal pyramids, and  an edgeedge with one I(1)K6 pentagonal pyramid. In the seventh P site, P(3) is bonded in a rectangular see-saw-like geometry to one K(1), one P(4), one P(7), and one P(8) atom. In the eighth P site, P(4) is bonded to one K(2), one P(3), one P(4), and one P(6) atom to form distorted PKP3 trigonal pyramids that share corners with two equivalent I(1)K6 pentagonal pyramids,  a cornercorner with one P(6)KP3 tetrahedra,  a cornercorner with one P(7)KP3 tetrahedra,  a cornercorner with one P(8)KP3 tetrahedra, corners with two equivalent P(4)KP3 trigonal pyramids, corners with three equivalent P(2)K2P2 trigonal pyramids, and  an edgeedge with one P(8)KP3 tetrahedra. I(1) is bonded to two equivalent K(1) and four equivalent K(2) atoms to form distorted IK6 pentagonal pyramids that share corners with two equivalent P(6)KP3 tetrahedra, corners with two equivalent P(7)KP3 tetrahedra, corners with eight equivalent P(8)KP3 tetrahedra, corners with four equivalent P(2)K2P2 trigonal pyramids, corners with eight equivalent P(4)KP3 trigonal pyramids, edges with two equivalent I(1)K6 pentagonal pyramids, and edges with two equivalent P(2)K2P2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4P21I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.745
_cell_length_b   12.745
_cell_length_c   9.810
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   118.115
_symmetry_Int_Tables_number   1
_cell_volume   1405.494
_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  0.246  0.070  0.250  1.0
  K  K1  1  0.754  0.930  0.750  1.0
  K  K2  1  0.070  0.246  0.250  1.0
  K  K3  1  0.930  0.754  0.750  1.0
  K  K4  1  0.379  0.621  0.500  1.0
  K  K5  1  0.621  0.379  0.000  1.0
  K  K6  1  0.621  0.379  0.500  1.0
  K  K7  1  0.379  0.621  0.000  1.0
  P  P8  1  0.961  0.961  0.250  1.0
  P  P9  1  0.039  0.039  0.750  1.0
  P  P10  1  0.664  0.210  0.250  1.0
  P  P11  1  0.336  0.790  0.750  1.0
  P  P12  1  0.210  0.664  0.250  1.0
  P  P13  1  0.790  0.336  0.750  1.0
  P  P14  1  0.310  0.008  0.924  1.0
  P  P15  1  0.690  0.992  0.424  1.0
  P  P16  1  0.008  0.310  0.576  1.0
  P  P17  1  0.992  0.690  0.076  1.0
  P  P18  1  0.060  0.502  0.916  1.0
  P  P19  1  0.940  0.498  0.416  1.0
  P  P20  1  0.502  0.060  0.584  1.0
  P  P21  1  0.498  0.940  0.084  1.0
  P  P22  1  0.940  0.498  0.084  1.0
  P  P23  1  0.060  0.502  0.584  1.0
  P  P24  1  0.498  0.940  0.416  1.0
  P  P25  1  0.502  0.060  0.916  1.0
  P  P26  1  0.146  0.146  0.914  1.0
  P  P27  1  0.854  0.854  0.414  1.0
  P  P28  1  0.146  0.146  0.586  1.0
  P  P29  1  0.854  0.854  0.086  1.0
  P  P30  1  0.945  0.507  0.750  1.0
  P  P31  1  0.055  0.493  0.250  1.0
  P  P32  1  0.507  0.945  0.750  1.0
  P  P33  1  0.493  0.055  0.250  1.0
  P  P34  1  0.880  0.231  0.750  1.0
  P  P35  1  0.120  0.769  0.250  1.0
  P  P36  1  0.231  0.880  0.750  1.0
  P  P37  1  0.769  0.120  0.250  1.0
  P  P38  1  0.181  0.330  0.865  1.0
  P  P39  1  0.819  0.670  0.365  1.0
  P  P40  1  0.330  0.181  0.635  1.0
  P  P41  1  0.670  0.819  0.135  1.0
  P  P42  1  0.819  0.670  0.135  1.0
  P  P43  1  0.181  0.330  0.635  1.0
  P  P44  1  0.670  0.819  0.365  1.0
  P  P45  1  0.330  0.181  0.865  1.0
  P  P46  1  0.008  0.310  0.924  1.0
  P  P47  1  0.992  0.690  0.424  1.0
  P  P48  1  0.310  0.008  0.576  1.0
  P  P49  1  0.690  0.992  0.076  1.0
  I  I50  1  0.398  0.398  0.250  1.0
  I  I51  1  0.602  0.602  0.750  1.0
[/CIF]
.
The material structure described by K4P21I crystallizes in the orthorhombic Cmcm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one P(1), one P(6), one P(7), two equivalent P(3), and one I(1) atom. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent P(2), two equivalent P(4), two equivalent P(8), and two equivalent I(1) atoms. There are eight inequivalent P sites. In the first P site, P(5) is bonded in a distorted trigonal non-coplanar geometry to one P(1) and two equivalent P(8) atoms. In the second P site, P(6) is bonded to one K(1), one P(2), and two equivalent P(4) atoms to form PKP3 tetrahedra that share  a cornercorner with one I(1)K6 pentagonal pyramid, corners with two equivalent P(7)KP3 tetrahedra, and corners with two equivalent P(4)KP3 trigonal pyramids. In the third P site, P(7) is bonded to one K(1), one P(2), and two equivalent P(3) atoms to form PKP3 tetrahedra that share  a cornercorner with one I(1)K6 pentagonal pyramid, corners with two equivalent P(6)KP3 tetrahedra, corners with two equivalent P(8)KP3 tetrahedra, and corners with two equivalent P(4)KP3 trigonal pyramids. In the fourth P site, P(8) is bonded to one K(2), one P(3), one P(5), and one P(8) atom to form PKP3 tetrahedra that share corners with two equivalent I(1)K6 pentagonal pyramids,  a cornercorner with one P(7)KP3 tetrahedra, corners with two equivalent P(8)KP3 tetrahedra,  a cornercorner with one P(4)KP3 trigonal pyramid, corners with two equivalent P(2)K2P2 trigonal pyramids, and  an edgeedge with one P(4)KP3 trigonal pyramid. In the fifth P site, P(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(1) and two equivalent P(5) atoms. In the sixth P site, P(2) is bonded to two equivalent K(2), one P(6), and one P(7) atom to form PK2P2 trigonal pyramids that share corners with two equivalent I(1)K6 pentagonal pyramids, corners with four equivalent P(8)KP3 tetrahedra, corners with two equivalent P(2)K2P2 trigonal pyramids, corners with six equivalent P(4)KP3 trigonal pyramids, and  an edgeedge with one I(1)K6 pentagonal pyramid. In the seventh P site, P(3) is bonded in a rectangular see-saw-like geometry to one K(1), one P(4), one P(7), and one P(8) atom. In the eighth P site, P(4) is bonded to one K(2), one P(3), one P(4), and one P(6) atom to form distorted PKP3 trigonal pyramids that share corners with two equivalent I(1)K6 pentagonal pyramids,  a cornercorner with one P(6)KP3 tetrahedra,  a cornercorner with one P(7)KP3 tetrahedra,  a cornercorner with one P(8)KP3 tetrahedra, corners with two equivalent P(4)KP3 trigonal pyramids, corners with three equivalent P(2)K2P2 trigonal pyramids, and  an edgeedge with one P(8)KP3 tetrahedra. I(1) is bonded to two equivalent K(1) and four equivalent K(2) atoms to form distorted IK6 pentagonal pyramids that share corners with two equivalent P(6)KP3 tetrahedra, corners with two equivalent P(7)KP3 tetrahedra, corners with eight equivalent P(8)KP3 tetrahedra, corners with four equivalent P(2)K2P2 trigonal pyramids, corners with eight equivalent P(4)KP3 trigonal pyramids, edges with two equivalent I(1)K6 pentagonal pyramids, and edges with two equivalent P(2)K2P2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4P21I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.745
_cell_length_b   12.745
_cell_length_c   9.810
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   118.115
_symmetry_Int_Tables_number   1
_cell_volume   1405.494
_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  0.246  0.070  0.250  1.0
  K  K1  1  0.754  0.930  0.750  1.0
  K  K2  1  0.070  0.246  0.250  1.0
  K  K3  1  0.930  0.754  0.750  1.0
  K  K4  1  0.379  0.621  0.500  1.0
  K  K5  1  0.621  0.379  0.000  1.0
  K  K6  1  0.621  0.379  0.500  1.0
  K  K7  1  0.379  0.621  0.000  1.0
  P  P8  1  0.961  0.961  0.250  1.0
  P  P9  1  0.039  0.039  0.750  1.0
  P  P10  1  0.664  0.210  0.250  1.0
  P  P11  1  0.336  0.790  0.750  1.0
  P  P12  1  0.210  0.664  0.250  1.0
  P  P13  1  0.790  0.336  0.750  1.0
  P  P14  1  0.310  0.008  0.924  1.0
  P  P15  1  0.690  0.992  0.424  1.0
  P  P16  1  0.008  0.310  0.576  1.0
  P  P17  1  0.992  0.690  0.076  1.0
  P  P18  1  0.060  0.502  0.916  1.0
  P  P19  1  0.940  0.498  0.416  1.0
  P  P20  1  0.502  0.060  0.584  1.0
  P  P21  1  0.498  0.940  0.084  1.0
  P  P22  1  0.940  0.498  0.084  1.0
  P  P23  1  0.060  0.502  0.584  1.0
  P  P24  1  0.498  0.940  0.416  1.0
  P  P25  1  0.502  0.060  0.916  1.0
  P  P26  1  0.146  0.146  0.914  1.0
  P  P27  1  0.854  0.854  0.414  1.0
  P  P28  1  0.146  0.146  0.586  1.0
  P  P29  1  0.854  0.854  0.086  1.0
  P  P30  1  0.945  0.507  0.750  1.0
  P  P31  1  0.055  0.493  0.250  1.0
  P  P32  1  0.507  0.945  0.750  1.0
  P  P33  1  0.493  0.055  0.250  1.0
  P  P34  1  0.880  0.231  0.750  1.0
  P  P35  1  0.120  0.769  0.250  1.0
  P  P36  1  0.231  0.880  0.750  1.0
  P  P37  1  0.769  0.120  0.250  1.0
  P  P38  1  0.181  0.330  0.865  1.0
  P  P39  1  0.819  0.670  0.365  1.0
  P  P40  1  0.330  0.181  0.635  1.0
  P  P41  1  0.670  0.819  0.135  1.0
  P  P42  1  0.819  0.670  0.135  1.0
  P  P43  1  0.181  0.330  0.635  1.0
  P  P44  1  0.670  0.819  0.365  1.0
  P  P45  1  0.330  0.181  0.865  1.0
  P  P46  1  0.008  0.310  0.924  1.0
  P  P47  1  0.992  0.690  0.424  1.0
  P  P48  1  0.310  0.008  0.576  1.0
  P  P49  1  0.690  0.992  0.076  1.0
  I  I50  1  0.398  0.398  0.250  1.0
  I  I51  1  0.602  0.602  0.750  1.0
[/CIF]
.