The structure described by MgSe2O5 crystallizes in the orthorhombic Pbcn space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form edge-sharing MgO6 octahedra. Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Se(1) atoms. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one Se(1) atom. is represented by the CIF card [CIF]
data_MgSe2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.018
_cell_length_b   6.826
_cell_length_c   10.395
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   427.025
_cell_formula_units_Z   4
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  0.750  0.000  0.561  1.0
  Mg  Mg1  1  0.250  0.500  0.939  1.0
  Mg  Mg2  1  0.250  0.000  0.439  1.0
  Mg  Mg3  1  0.750  0.500  0.061  1.0
  Se  Se4  1  0.529  0.133  0.846  1.0
  Se  Se5  1  0.029  0.367  0.654  1.0
  Se  Se6  1  0.471  0.633  0.654  1.0
  Se  Se7  1  0.971  0.867  0.846  1.0
  Se  Se8  1  0.471  0.867  0.154  1.0
  Se  Se9  1  0.971  0.633  0.346  1.0
  Se  Se10  1  0.529  0.367  0.346  1.0
  Se  Se11  1  0.029  0.133  0.154  1.0
  O  O12  1  0.250  0.500  0.568  1.0
  O  O13  1  0.750  0.000  0.932  1.0
  O  O14  1  0.750  0.500  0.432  1.0
  O  O15  1  0.250  0.000  0.068  1.0
  O  O16  1  0.658  0.192  0.708  1.0
  O  O17  1  0.158  0.308  0.792  1.0
  O  O18  1  0.342  0.692  0.792  1.0
  O  O19  1  0.842  0.808  0.708  1.0
  O  O20  1  0.342  0.808  0.292  1.0
  O  O21  1  0.842  0.692  0.208  1.0
  O  O22  1  0.658  0.308  0.208  1.0
  O  O23  1  0.158  0.192  0.292  1.0
  O  O24  1  0.047  0.342  0.067  1.0
  O  O25  1  0.547  0.158  0.433  1.0
  O  O26  1  0.953  0.842  0.433  1.0
  O  O27  1  0.453  0.658  0.067  1.0
  O  O28  1  0.953  0.658  0.933  1.0
  O  O29  1  0.453  0.842  0.567  1.0
  O  O30  1  0.047  0.158  0.567  1.0
  O  O31  1  0.547  0.342  0.933  1.0
[/CIF]
.
The structure described by MgSe2O5 crystallizes in the orthorhombic Pbcn space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form edge-sharing MgO6 octahedra. Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Se(1) atoms. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one Se(1) atom. is represented by the CIF card [CIF]
data_MgSe2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.018
_cell_length_b   6.826
_cell_length_c   10.395
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   427.025
_cell_formula_units_Z   4
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  0.750  0.000  0.561  1.0
  Mg  Mg1  1  0.250  0.500  0.939  1.0
  Mg  Mg2  1  0.250  0.000  0.439  1.0
  Mg  Mg3  1  0.750  0.500  0.061  1.0
  Se  Se4  1  0.529  0.133  0.846  1.0
  Se  Se5  1  0.029  0.367  0.654  1.0
  Se  Se6  1  0.471  0.633  0.654  1.0
  Se  Se7  1  0.971  0.867  0.846  1.0
  Se  Se8  1  0.471  0.867  0.154  1.0
  Se  Se9  1  0.971  0.633  0.346  1.0
  Se  Se10  1  0.529  0.367  0.346  1.0
  Se  Se11  1  0.029  0.133  0.154  1.0
  O  O12  1  0.250  0.500  0.568  1.0
  O  O13  1  0.750  0.000  0.932  1.0
  O  O14  1  0.750  0.500  0.432  1.0
  O  O15  1  0.250  0.000  0.068  1.0
  O  O16  1  0.658  0.192  0.708  1.0
  O  O17  1  0.158  0.308  0.792  1.0
  O  O18  1  0.342  0.692  0.792  1.0
  O  O19  1  0.842  0.808  0.708  1.0
  O  O20  1  0.342  0.808  0.292  1.0
  O  O21  1  0.842  0.692  0.208  1.0
  O  O22  1  0.658  0.308  0.208  1.0
  O  O23  1  0.158  0.192  0.292  1.0
  O  O24  1  0.047  0.342  0.067  1.0
  O  O25  1  0.547  0.158  0.433  1.0
  O  O26  1  0.953  0.842  0.433  1.0
  O  O27  1  0.453  0.658  0.067  1.0
  O  O28  1  0.953  0.658  0.933  1.0
  O  O29  1  0.453  0.842  0.567  1.0
  O  O30  1  0.047  0.158  0.567  1.0
  O  O31  1  0.547  0.342  0.933  1.0
[/CIF]
.