The crystal structure described by MgU2Si2O17 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(6) atoms to form distorted MgO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra. U(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), and four equivalent O(5) atoms. Si(1) is bonded to one O(3), one O(4), and two equivalent O(5) atoms to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one U(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one U(1) atom. In the third O site, O(3) is bonded in a linear geometry to one Mg(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one U(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent U(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Mg(1) and one O(7) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(6) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgU2Si2O17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.386
_cell_length_b   9.386
_cell_length_c   6.731
_cell_angle_alpha   78.075
_cell_angle_beta   78.075
_cell_angle_gamma   44.017
_symmetry_Int_Tables_number   1
_cell_volume   401.645
_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
  Mg  Mg0  1  0.000  0.000  0.500  1.0
  U  U1  1  0.261  0.261  0.851  1.0
  U  U2  1  0.739  0.739  0.149  1.0
  Si  Si3  1  0.209  0.209  0.347  1.0
  Si  Si4  1  0.791  0.791  0.653  1.0
  O  O5  1  0.154  0.154  0.922  1.0
  O  O6  1  0.846  0.846  0.078  1.0
  O  O7  1  0.367  0.367  0.821  1.0
  O  O8  1  0.633  0.633  0.179  1.0
  O  O9  1  0.115  0.115  0.437  1.0
  O  O10  1  0.885  0.885  0.563  1.0
  O  O11  1  0.253  0.253  0.537  1.0
  O  O12  1  0.747  0.747  0.463  1.0
  O  O13  1  0.059  0.418  0.191  1.0
  O  O14  1  0.418  0.059  0.191  1.0
  O  O15  1  0.941  0.582  0.809  1.0
  O  O16  1  0.582  0.941  0.809  1.0
  O  O17  1  0.865  0.150  0.208  1.0
  O  O18  1  0.150  0.865  0.208  1.0
  O  O19  1  0.135  0.850  0.792  1.0
  O  O20  1  0.850  0.135  0.792  1.0
  O  O21  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by MgU2Si2O17 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(6) atoms to form distorted MgO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra. U(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), and four equivalent O(5) atoms. Si(1) is bonded to one O(3), one O(4), and two equivalent O(5) atoms to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one U(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one U(1) atom. In the third O site, O(3) is bonded in a linear geometry to one Mg(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one U(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent U(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Mg(1) and one O(7) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(6) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgU2Si2O17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.386
_cell_length_b   9.386
_cell_length_c   6.731
_cell_angle_alpha   78.075
_cell_angle_beta   78.075
_cell_angle_gamma   44.017
_symmetry_Int_Tables_number   1
_cell_volume   401.645
_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
  Mg  Mg0  1  0.000  0.000  0.500  1.0
  U  U1  1  0.261  0.261  0.851  1.0
  U  U2  1  0.739  0.739  0.149  1.0
  Si  Si3  1  0.209  0.209  0.347  1.0
  Si  Si4  1  0.791  0.791  0.653  1.0
  O  O5  1  0.154  0.154  0.922  1.0
  O  O6  1  0.846  0.846  0.078  1.0
  O  O7  1  0.367  0.367  0.821  1.0
  O  O8  1  0.633  0.633  0.179  1.0
  O  O9  1  0.115  0.115  0.437  1.0
  O  O10  1  0.885  0.885  0.563  1.0
  O  O11  1  0.253  0.253  0.537  1.0
  O  O12  1  0.747  0.747  0.463  1.0
  O  O13  1  0.059  0.418  0.191  1.0
  O  O14  1  0.418  0.059  0.191  1.0
  O  O15  1  0.941  0.582  0.809  1.0
  O  O16  1  0.582  0.941  0.809  1.0
  O  O17  1  0.865  0.150  0.208  1.0
  O  O18  1  0.150  0.865  0.208  1.0
  O  O19  1  0.135  0.850  0.792  1.0
  O  O20  1  0.850  0.135  0.792  1.0
  O  O21  1  0.000  0.000  0.000  1.0
[/CIF]
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