The crystal structure described by SrU2Se5 crystallizes in the orthorhombic Pnma space group. Sr(1) is bonded to one Se(2), one Se(3), one Se(4), and four equivalent Se(1) atoms to form distorted edge-sharing SrSe7 pentagonal bipyramids. U(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Sr(1) and two equivalent U(1) atoms to form distorted SeSr2U2 tetrahedra that share corners with two equivalent Se(4)SrU4 square pyramids, corners with four equivalent Se(3)SrU4 square pyramids, corners with six equivalent Se(1)Sr2U2 tetrahedra, corners with two equivalent Se(2)SrU4 trigonal bipyramids,  an edgeedge with one Se(3)SrU4 square pyramid, edges with two equivalent Se(4)SrU4 square pyramids,  an edgeedge with one Se(1)Sr2U2 tetrahedra, and edges with two equivalent Se(2)SrU4 trigonal bipyramids. In the second Se site, Se(2) is bonded to one Sr(1) and four equivalent U(1) atoms to form distorted SeSrU4 trigonal bipyramids that share  a cornercorner with one Se(4)SrU4 square pyramid, corners with five equivalent Se(3)SrU4 square pyramids, corners with four equivalent Se(1)Sr2U2 tetrahedra, corners with four equivalent Se(2)SrU4 trigonal bipyramids, edges with two equivalent Se(3)SrU4 square pyramids, edges with four equivalent Se(4)SrU4 square pyramids, and edges with four equivalent Se(1)Sr2U2 tetrahedra. In the third Se site, Se(3) is bonded to one Sr(1) and four equivalent U(1) atoms to form SeSrU4 square pyramids that share corners with four equivalent Se(4)SrU4 square pyramids, corners with eight equivalent Se(1)Sr2U2 tetrahedra, corners with five equivalent Se(2)SrU4 trigonal bipyramids,  an edgeedge with one Se(4)SrU4 square pyramid, edges with two equivalent Se(3)SrU4 square pyramids, edges with two equivalent Se(1)Sr2U2 tetrahedra, edges with two equivalent Se(2)SrU4 trigonal bipyramids, and  a faceface with one Se(4)SrU4 square pyramid. In the fourth Se site, Se(4) is bonded to one Sr(1) and four equivalent U(1) atoms to form SeSrU4 square pyramids that share corners with four equivalent Se(3)SrU4 square pyramids, corners with four equivalent Se(4)SrU4 square pyramids, corners with four equivalent Se(1)Sr2U2 tetrahedra,  a cornercorner with one Se(2)SrU4 trigonal bipyramid,  an edgeedge with one Se(3)SrU4 square pyramid, edges with four equivalent Se(1)Sr2U2 tetrahedra, edges with four equivalent Se(2)SrU4 trigonal bipyramids, and  a faceface with one Se(3)SrU4 square pyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrU2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.742
_cell_length_b   8.216
_cell_length_c   12.863
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   818.203
_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
  Sr  Sr0  1  0.419  0.750  0.006  1.0
  Sr  Sr1  1  0.081  0.750  0.506  1.0
  Sr  Sr2  1  0.581  0.250  0.994  1.0
  Sr  Sr3  1  0.919  0.250  0.494  1.0
  U  U4  1  0.988  0.999  0.182  1.0
  U  U5  1  0.512  0.501  0.682  1.0
  U  U6  1  0.012  0.499  0.818  1.0
  U  U7  1  0.488  0.001  0.318  1.0
  U  U8  1  0.012  0.001  0.818  1.0
  U  U9  1  0.488  0.499  0.318  1.0
  U  U10  1  0.988  0.501  0.182  1.0
  U  U11  1  0.512  0.999  0.682  1.0
  Se  Se12  1  0.669  0.548  0.881  1.0
  Se  Se13  1  0.831  0.952  0.381  1.0
  Se  Se14  1  0.331  0.048  0.119  1.0
  Se  Se15  1  0.169  0.452  0.619  1.0
  Se  Se16  1  0.331  0.452  0.119  1.0
  Se  Se17  1  0.169  0.048  0.619  1.0
  Se  Se18  1  0.669  0.952  0.881  1.0
  Se  Se19  1  0.831  0.548  0.381  1.0
  Se  Se20  1  0.678  0.750  0.185  1.0
  Se  Se21  1  0.822  0.750  0.685  1.0
  Se  Se22  1  0.322  0.250  0.815  1.0
  Se  Se23  1  0.178  0.250  0.315  1.0
  Se  Se24  1  0.019  0.750  0.001  1.0
  Se  Se25  1  0.481  0.750  0.501  1.0
  Se  Se26  1  0.981  0.250  0.999  1.0
  Se  Se27  1  0.519  0.250  0.499  1.0
  Se  Se28  1  0.291  0.750  0.783  1.0
  Se  Se29  1  0.209  0.750  0.283  1.0
  Se  Se30  1  0.709  0.250  0.217  1.0
  Se  Se31  1  0.791  0.250  0.717  1.0
[/CIF]
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The crystal structure described by SrU2Se5 crystallizes in the orthorhombic Pnma space group. Sr(1) is bonded to one Se(2), one Se(3), one Se(4), and four equivalent Se(1) atoms to form distorted edge-sharing SrSe7 pentagonal bipyramids. U(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Sr(1) and two equivalent U(1) atoms to form distorted SeSr2U2 tetrahedra that share corners with two equivalent Se(4)SrU4 square pyramids, corners with four equivalent Se(3)SrU4 square pyramids, corners with six equivalent Se(1)Sr2U2 tetrahedra, corners with two equivalent Se(2)SrU4 trigonal bipyramids,  an edgeedge with one Se(3)SrU4 square pyramid, edges with two equivalent Se(4)SrU4 square pyramids,  an edgeedge with one Se(1)Sr2U2 tetrahedra, and edges with two equivalent Se(2)SrU4 trigonal bipyramids. In the second Se site, Se(2) is bonded to one Sr(1) and four equivalent U(1) atoms to form distorted SeSrU4 trigonal bipyramids that share  a cornercorner with one Se(4)SrU4 square pyramid, corners with five equivalent Se(3)SrU4 square pyramids, corners with four equivalent Se(1)Sr2U2 tetrahedra, corners with four equivalent Se(2)SrU4 trigonal bipyramids, edges with two equivalent Se(3)SrU4 square pyramids, edges with four equivalent Se(4)SrU4 square pyramids, and edges with four equivalent Se(1)Sr2U2 tetrahedra. In the third Se site, Se(3) is bonded to one Sr(1) and four equivalent U(1) atoms to form SeSrU4 square pyramids that share corners with four equivalent Se(4)SrU4 square pyramids, corners with eight equivalent Se(1)Sr2U2 tetrahedra, corners with five equivalent Se(2)SrU4 trigonal bipyramids,  an edgeedge with one Se(4)SrU4 square pyramid, edges with two equivalent Se(3)SrU4 square pyramids, edges with two equivalent Se(1)Sr2U2 tetrahedra, edges with two equivalent Se(2)SrU4 trigonal bipyramids, and  a faceface with one Se(4)SrU4 square pyramid. In the fourth Se site, Se(4) is bonded to one Sr(1) and four equivalent U(1) atoms to form SeSrU4 square pyramids that share corners with four equivalent Se(3)SrU4 square pyramids, corners with four equivalent Se(4)SrU4 square pyramids, corners with four equivalent Se(1)Sr2U2 tetrahedra,  a cornercorner with one Se(2)SrU4 trigonal bipyramid,  an edgeedge with one Se(3)SrU4 square pyramid, edges with four equivalent Se(1)Sr2U2 tetrahedra, edges with four equivalent Se(2)SrU4 trigonal bipyramids, and  a faceface with one Se(3)SrU4 square pyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrU2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.742
_cell_length_b   8.216
_cell_length_c   12.863
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   818.203
_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
  Sr  Sr0  1  0.419  0.750  0.006  1.0
  Sr  Sr1  1  0.081  0.750  0.506  1.0
  Sr  Sr2  1  0.581  0.250  0.994  1.0
  Sr  Sr3  1  0.919  0.250  0.494  1.0
  U  U4  1  0.988  0.999  0.182  1.0
  U  U5  1  0.512  0.501  0.682  1.0
  U  U6  1  0.012  0.499  0.818  1.0
  U  U7  1  0.488  0.001  0.318  1.0
  U  U8  1  0.012  0.001  0.818  1.0
  U  U9  1  0.488  0.499  0.318  1.0
  U  U10  1  0.988  0.501  0.182  1.0
  U  U11  1  0.512  0.999  0.682  1.0
  Se  Se12  1  0.669  0.548  0.881  1.0
  Se  Se13  1  0.831  0.952  0.381  1.0
  Se  Se14  1  0.331  0.048  0.119  1.0
  Se  Se15  1  0.169  0.452  0.619  1.0
  Se  Se16  1  0.331  0.452  0.119  1.0
  Se  Se17  1  0.169  0.048  0.619  1.0
  Se  Se18  1  0.669  0.952  0.881  1.0
  Se  Se19  1  0.831  0.548  0.381  1.0
  Se  Se20  1  0.678  0.750  0.185  1.0
  Se  Se21  1  0.822  0.750  0.685  1.0
  Se  Se22  1  0.322  0.250  0.815  1.0
  Se  Se23  1  0.178  0.250  0.315  1.0
  Se  Se24  1  0.019  0.750  0.001  1.0
  Se  Se25  1  0.481  0.750  0.501  1.0
  Se  Se26  1  0.981  0.250  0.999  1.0
  Se  Se27  1  0.519  0.250  0.499  1.0
  Se  Se28  1  0.291  0.750  0.783  1.0
  Se  Se29  1  0.209  0.750  0.283  1.0
  Se  Se30  1  0.709  0.250  0.217  1.0
  Se  Se31  1  0.791  0.250  0.717  1.0
[/CIF]
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