The compound described by Na2Th(AsO4)2 is Esseneite-like structured and crystallizes in the orthorhombic Fddd space group. Na(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted NaO6 pentagonal pyramids that share corners with four equivalent As(1)O4 tetrahedra, edges with two equivalent Na(1)O6 pentagonal pyramids, and  an edgeedge with one As(1)O4 tetrahedra. Th(1) is bonded in a distorted body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. As(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form AsO4 tetrahedra that share corners with four equivalent Na(1)O6 pentagonal pyramids and  an edgeedge with one Na(1)O6 pentagonal pyramid. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Th(1), and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Th(1), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2Th(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.149
_cell_length_b   9.922
_cell_length_c   7.178
_cell_angle_alpha   79.624
_cell_angle_beta   61.085
_cell_angle_gamma   39.291
_symmetry_Int_Tables_number   1
_cell_volume   412.275
_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
  Na  Na0  1  0.893  0.893  0.607  1.0
  Na  Na1  1  0.607  0.607  0.893  1.0
  Na  Na2  1  0.357  0.357  0.643  1.0
  Na  Na3  1  0.643  0.643  0.357  1.0
  Th  Th4  1  0.250  0.250  0.250  1.0
  Th  Th5  1  0.000  0.000  0.000  1.0
  As  As6  1  0.071  0.071  0.429  1.0
  As  As7  1  0.429  0.429  0.071  1.0
  As  As8  1  0.179  0.179  0.821  1.0
  As  As9  1  0.821  0.821  0.179  1.0
  O  O10  1  0.341  0.920  0.229  1.0
  O  O11  1  0.510  0.229  0.920  1.0
  O  O12  1  0.229  0.510  0.341  1.0
  O  O13  1  0.920  0.341  0.510  1.0
  O  O14  1  0.909  0.330  0.021  1.0
  O  O15  1  0.740  0.021  0.330  1.0
  O  O16  1  0.021  0.740  0.909  1.0
  O  O17  1  0.330  0.909  0.740  1.0
  O  O18  1  0.070  0.957  0.638  1.0
  O  O19  1  0.334  0.638  0.957  1.0
  O  O20  1  0.638  0.334  0.070  1.0
  O  O21  1  0.957  0.070  0.334  1.0
  O  O22  1  0.180  0.293  0.612  1.0
  O  O23  1  0.916  0.612  0.293  1.0
  O  O24  1  0.612  0.916  0.180  1.0
  O  O25  1  0.293  0.180  0.916  1.0
[/CIF]
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The compound described by Na2Th(AsO4)2 is Esseneite-like structured and crystallizes in the orthorhombic Fddd space group. Na(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted NaO6 pentagonal pyramids that share corners with four equivalent As(1)O4 tetrahedra, edges with two equivalent Na(1)O6 pentagonal pyramids, and  an edgeedge with one As(1)O4 tetrahedra. Th(1) is bonded in a distorted body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. As(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form AsO4 tetrahedra that share corners with four equivalent Na(1)O6 pentagonal pyramids and  an edgeedge with one Na(1)O6 pentagonal pyramid. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Th(1), and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Th(1), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2Th(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.149
_cell_length_b   9.922
_cell_length_c   7.178
_cell_angle_alpha   79.624
_cell_angle_beta   61.085
_cell_angle_gamma   39.291
_symmetry_Int_Tables_number   1
_cell_volume   412.275
_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
  Na  Na0  1  0.893  0.893  0.607  1.0
  Na  Na1  1  0.607  0.607  0.893  1.0
  Na  Na2  1  0.357  0.357  0.643  1.0
  Na  Na3  1  0.643  0.643  0.357  1.0
  Th  Th4  1  0.250  0.250  0.250  1.0
  Th  Th5  1  0.000  0.000  0.000  1.0
  As  As6  1  0.071  0.071  0.429  1.0
  As  As7  1  0.429  0.429  0.071  1.0
  As  As8  1  0.179  0.179  0.821  1.0
  As  As9  1  0.821  0.821  0.179  1.0
  O  O10  1  0.341  0.920  0.229  1.0
  O  O11  1  0.510  0.229  0.920  1.0
  O  O12  1  0.229  0.510  0.341  1.0
  O  O13  1  0.920  0.341  0.510  1.0
  O  O14  1  0.909  0.330  0.021  1.0
  O  O15  1  0.740  0.021  0.330  1.0
  O  O16  1  0.021  0.740  0.909  1.0
  O  O17  1  0.330  0.909  0.740  1.0
  O  O18  1  0.070  0.957  0.638  1.0
  O  O19  1  0.334  0.638  0.957  1.0
  O  O20  1  0.638  0.334  0.070  1.0
  O  O21  1  0.957  0.070  0.334  1.0
  O  O22  1  0.180  0.293  0.612  1.0
  O  O23  1  0.916  0.612  0.293  1.0
  O  O24  1  0.612  0.916  0.180  1.0
  O  O25  1  0.293  0.180  0.916  1.0
[/CIF]
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