The material structure described by K4MgV6O16 crystallizes in the monoclinic Cm space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. In the second K site, K(2) is bonded in a 9-coordinate geometry to two equivalent Mg(1), one O(4), two equivalent O(1), two equivalent O(5), and two equivalent O(7) atoms. In the third K site, K(3) is bonded to one O(3), one O(6), two equivalent O(5), and two equivalent O(8) atoms to form distorted KO6 octahedra that share  a cornercorner with one V(2)O4 tetrahedra, corners with four equivalent V(1)O4 tetrahedra, and  an edgeedge with one V(2)O4 tetrahedra. Mg(1) is bonded in a 5-coordinate geometry to two equivalent K(2), one O(3), two equivalent O(10), and two equivalent O(7) atoms. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(10), one O(3), one O(5), and one O(9) atom to form VO4 tetrahedra that share corners with two equivalent K(3)O6 octahedra and  a cornercorner with one V(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 67-73°. In the second V site, V(2) is bonded to one O(2), one O(6), and two equivalent O(8) atoms to form VO4 tetrahedra that share  a cornercorner with one K(3)O6 octahedra,  a cornercorner with one V(3)O4 tetrahedra, and  an edgeedge with one K(3)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the third V site, V(3) is bonded to one O(2), one O(4), and two equivalent O(7) atoms to form corner-sharing VO4 tetrahedra. In the fourth V site, V(4) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(7), one O(8), and one O(9) atom. There are ten inequivalent O sites. In the first O site, O(9) is bonded in a distorted bent 150 degrees geometry to one K(1), one V(1), and one V(4) atom. In the second O site, O(10) is bonded in a 3-coordinate geometry to one K(1), one Mg(1), one V(1), and one V(4) atom. In the third O site, O(1) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one V(4) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to two equivalent K(1), one V(2), and one V(3) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one K(3), one Mg(1), and two equivalent V(1) atoms. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), and one V(3) atom. In the seventh O site, O(5) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(3), and one V(1) atom. In the eighth O site, O(6) is bonded in a distorted single-bond geometry to one K(3), two equivalent K(1), and one V(2) atom. In the ninth O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one K(2), one Mg(1), one V(3), and one V(4) atom. In the tenth O site, O(8) is bonded in a 4-coordinate geometry to one K(1), one K(3), one V(2), and one V(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4MgV6O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.014
_cell_length_b   8.963
_cell_length_c   8.963
_cell_angle_alpha   92.983
_cell_angle_beta   89.238
_cell_angle_gamma   90.762
_symmetry_Int_Tables_number   1
_cell_volume   482.371
_cell_formula_units_Z   1
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  0.179  0.631  0.211  1.0
  K  K1  1  0.056  0.813  0.687  1.0
  K  K2  1  0.183  0.165  0.335  1.0
  K  K3  1  0.179  0.289  0.869  1.0
  Mg  Mg4  1  0.546  0.835  0.665  1.0
  V  V5  1  0.677  0.875  0.345  1.0
  V  V6  1  0.629  0.357  0.143  1.0
  V  V7  1  0.677  0.155  0.625  1.0
  V  V8  1  0.688  0.612  0.888  1.0
  V  V9  1  0.650  0.001  0.981  1.0
  V  V10  1  0.650  0.519  0.499  1.0
  O  O11  1  0.922  0.531  0.470  1.0
  O  O12  1  0.922  0.030  0.969  1.0
  O  O13  1  0.528  0.489  0.011  1.0
  O  O14  1  0.576  0.021  0.479  1.0
  O  O15  1  0.969  0.611  0.889  1.0
  O  O16  1  0.956  0.139  0.632  1.0
  O  O17  1  0.956  0.868  0.361  1.0
  O  O18  1  0.907  0.353  0.147  1.0
  O  O19  1  0.586  0.614  0.691  1.0
  O  O20  1  0.513  0.420  0.315  1.0
  O  O21  1  0.513  0.185  0.080  1.0
  O  O22  1  0.570  0.903  0.168  1.0
  O  O23  1  0.536  0.052  0.775  1.0
  O  O24  1  0.586  0.809  0.886  1.0
  O  O25  1  0.570  0.332  0.597  1.0
  O  O26  1  0.536  0.725  0.448  1.0
[/CIF]
.
The material structure described by K4MgV6O16 crystallizes in the monoclinic Cm space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. In the second K site, K(2) is bonded in a 9-coordinate geometry to two equivalent Mg(1), one O(4), two equivalent O(1), two equivalent O(5), and two equivalent O(7) atoms. In the third K site, K(3) is bonded to one O(3), one O(6), two equivalent O(5), and two equivalent O(8) atoms to form distorted KO6 octahedra that share  a cornercorner with one V(2)O4 tetrahedra, corners with four equivalent V(1)O4 tetrahedra, and  an edgeedge with one V(2)O4 tetrahedra. Mg(1) is bonded in a 5-coordinate geometry to two equivalent K(2), one O(3), two equivalent O(10), and two equivalent O(7) atoms. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(10), one O(3), one O(5), and one O(9) atom to form VO4 tetrahedra that share corners with two equivalent K(3)O6 octahedra and  a cornercorner with one V(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 67-73°. In the second V site, V(2) is bonded to one O(2), one O(6), and two equivalent O(8) atoms to form VO4 tetrahedra that share  a cornercorner with one K(3)O6 octahedra,  a cornercorner with one V(3)O4 tetrahedra, and  an edgeedge with one K(3)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the third V site, V(3) is bonded to one O(2), one O(4), and two equivalent O(7) atoms to form corner-sharing VO4 tetrahedra. In the fourth V site, V(4) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(7), one O(8), and one O(9) atom. There are ten inequivalent O sites. In the first O site, O(9) is bonded in a distorted bent 150 degrees geometry to one K(1), one V(1), and one V(4) atom. In the second O site, O(10) is bonded in a 3-coordinate geometry to one K(1), one Mg(1), one V(1), and one V(4) atom. In the third O site, O(1) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one V(4) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to two equivalent K(1), one V(2), and one V(3) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one K(3), one Mg(1), and two equivalent V(1) atoms. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), and one V(3) atom. In the seventh O site, O(5) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(3), and one V(1) atom. In the eighth O site, O(6) is bonded in a distorted single-bond geometry to one K(3), two equivalent K(1), and one V(2) atom. In the ninth O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one K(2), one Mg(1), one V(3), and one V(4) atom. In the tenth O site, O(8) is bonded in a 4-coordinate geometry to one K(1), one K(3), one V(2), and one V(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4MgV6O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.014
_cell_length_b   8.963
_cell_length_c   8.963
_cell_angle_alpha   92.983
_cell_angle_beta   89.238
_cell_angle_gamma   90.762
_symmetry_Int_Tables_number   1
_cell_volume   482.371
_cell_formula_units_Z   1
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  0.179  0.631  0.211  1.0
  K  K1  1  0.056  0.813  0.687  1.0
  K  K2  1  0.183  0.165  0.335  1.0
  K  K3  1  0.179  0.289  0.869  1.0
  Mg  Mg4  1  0.546  0.835  0.665  1.0
  V  V5  1  0.677  0.875  0.345  1.0
  V  V6  1  0.629  0.357  0.143  1.0
  V  V7  1  0.677  0.155  0.625  1.0
  V  V8  1  0.688  0.612  0.888  1.0
  V  V9  1  0.650  0.001  0.981  1.0
  V  V10  1  0.650  0.519  0.499  1.0
  O  O11  1  0.922  0.531  0.470  1.0
  O  O12  1  0.922  0.030  0.969  1.0
  O  O13  1  0.528  0.489  0.011  1.0
  O  O14  1  0.576  0.021  0.479  1.0
  O  O15  1  0.969  0.611  0.889  1.0
  O  O16  1  0.956  0.139  0.632  1.0
  O  O17  1  0.956  0.868  0.361  1.0
  O  O18  1  0.907  0.353  0.147  1.0
  O  O19  1  0.586  0.614  0.691  1.0
  O  O20  1  0.513  0.420  0.315  1.0
  O  O21  1  0.513  0.185  0.080  1.0
  O  O22  1  0.570  0.903  0.168  1.0
  O  O23  1  0.536  0.052  0.775  1.0
  O  O24  1  0.586  0.809  0.886  1.0
  O  O25  1  0.570  0.332  0.597  1.0
  O  O26  1  0.536  0.725  0.448  1.0
[/CIF]
.