The structure described by U4O7 crystallizes in the monoclinic C2/c space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second U site, U(2) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the second O site, O(2) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the third O site, O(3) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the fourth O site, O(4) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. is represented by the CIF file [CIF]
data_U4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.651
_cell_length_b   6.651
_cell_length_c   10.854
_cell_angle_alpha   65.974
_cell_angle_beta   65.974
_cell_angle_gamma   48.541
_symmetry_Int_Tables_number   1
_cell_volume   321.972
_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
  U  U0  1  0.147  0.112  0.316  1.0
  U  U1  1  0.619  0.638  0.056  1.0
  U  U2  1  0.362  0.381  0.444  1.0
  U  U3  1  0.853  0.888  0.684  1.0
  U  U4  1  0.888  0.853  0.184  1.0
  U  U5  1  0.381  0.362  0.944  1.0
  U  U6  1  0.638  0.619  0.556  1.0
  U  U7  1  0.112  0.147  0.816  1.0
  O  O8  1  0.993  0.486  0.131  1.0
  O  O9  1  0.504  0.998  0.124  1.0
  O  O10  1  0.253  0.753  0.511  1.0
  O  O11  1  0.753  0.253  0.011  1.0
  O  O12  1  0.254  0.746  0.250  1.0
  O  O13  1  0.747  0.247  0.489  1.0
  O  O14  1  0.247  0.747  0.989  1.0
  O  O15  1  0.496  0.002  0.876  1.0
  O  O16  1  0.998  0.504  0.624  1.0
  O  O17  1  0.007  0.514  0.869  1.0
  O  O18  1  0.486  0.993  0.631  1.0
  O  O19  1  0.002  0.496  0.376  1.0
  O  O20  1  0.514  0.007  0.369  1.0
  O  O21  1  0.746  0.254  0.750  1.0
[/CIF]
.
The structure described by U4O7 crystallizes in the monoclinic C2/c space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second U site, U(2) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the second O site, O(2) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the third O site, O(3) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the fourth O site, O(4) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. is represented by the CIF file [CIF]
data_U4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.651
_cell_length_b   6.651
_cell_length_c   10.854
_cell_angle_alpha   65.974
_cell_angle_beta   65.974
_cell_angle_gamma   48.541
_symmetry_Int_Tables_number   1
_cell_volume   321.972
_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
  U  U0  1  0.147  0.112  0.316  1.0
  U  U1  1  0.619  0.638  0.056  1.0
  U  U2  1  0.362  0.381  0.444  1.0
  U  U3  1  0.853  0.888  0.684  1.0
  U  U4  1  0.888  0.853  0.184  1.0
  U  U5  1  0.381  0.362  0.944  1.0
  U  U6  1  0.638  0.619  0.556  1.0
  U  U7  1  0.112  0.147  0.816  1.0
  O  O8  1  0.993  0.486  0.131  1.0
  O  O9  1  0.504  0.998  0.124  1.0
  O  O10  1  0.253  0.753  0.511  1.0
  O  O11  1  0.753  0.253  0.011  1.0
  O  O12  1  0.254  0.746  0.250  1.0
  O  O13  1  0.747  0.247  0.489  1.0
  O  O14  1  0.247  0.747  0.989  1.0
  O  O15  1  0.496  0.002  0.876  1.0
  O  O16  1  0.998  0.504  0.624  1.0
  O  O17  1  0.007  0.514  0.869  1.0
  O  O18  1  0.486  0.993  0.631  1.0
  O  O19  1  0.002  0.496  0.376  1.0
  O  O20  1  0.514  0.007  0.369  1.0
  O  O21  1  0.746  0.254  0.750  1.0
[/CIF]
.