The crystal structure described by SmZr4O9 crystallizes in the orthorhombic Imm2 space group. Sm(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one O(2), one O(3), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of distorted edge and corner-sharing ZrO7 hexagonal pyramids. In the second Zr site, Zr(2) is bonded in a body-centered cubic geometry to one O(1), one O(4), three equivalent O(3), and three equivalent O(5) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Sm(1), one Zr(2), and two equivalent Zr(1) atoms to form OSmZr3 tetrahedra that share  a cornercorner with one O(5)Zr4 tetrahedra, corners with three equivalent O(1)SmZr3 tetrahedra, corners with three equivalent O(4)SmZr3 tetrahedra, corners with five equivalent O(3)Zr4 tetrahedra, edges with two equivalent O(4)SmZr3 tetrahedra, and edges with two equivalent O(5)Zr4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sm(1) and two equivalent Zr(1) atoms. In the third O site, O(3) is bonded to one Zr(1) and three equivalent Zr(2) atoms to form OZr4 tetrahedra that share  a cornercorner with one O(4)SmZr3 tetrahedra, corners with two equivalent O(5)Zr4 tetrahedra, corners with five equivalent O(1)SmZr3 tetrahedra, corners with six equivalent O(3)Zr4 tetrahedra, edges with two equivalent O(4)SmZr3 tetrahedra, and edges with four equivalent O(5)Zr4 tetrahedra. In the fourth O site, O(4) is bonded to one Sm(1), one Zr(2), and two equivalent Zr(1) atoms to form OSmZr3 tetrahedra that share  a cornercorner with one O(3)Zr4 tetrahedra, corners with three equivalent O(1)SmZr3 tetrahedra, corners with three equivalent O(4)SmZr3 tetrahedra, corners with five equivalent O(5)Zr4 tetrahedra, edges with two equivalent O(1)SmZr3 tetrahedra, and edges with two equivalent O(3)Zr4 tetrahedra. In the fifth O site, O(5) is bonded to one Zr(1) and three equivalent Zr(2) atoms to form OZr4 tetrahedra that share  a cornercorner with one O(1)SmZr3 tetrahedra, corners with two equivalent O(3)Zr4 tetrahedra, corners with five equivalent O(4)SmZr3 tetrahedra, corners with six equivalent O(5)Zr4 tetrahedra, edges with two equivalent O(1)SmZr3 tetrahedra, and edges with four equivalent O(3)Zr4 tetrahedra. is represented by the CIF file [CIF]
data_SmZr4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.944
_cell_length_b   9.944
_cell_length_c   9.944
_cell_angle_alpha   159.332
_cell_angle_beta   149.450
_cell_angle_gamma   37.171
_symmetry_Int_Tables_number   1
_cell_volume   176.185
_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
  Sm  Sm0  1  0.015  0.000  0.015  1.0
  Zr  Zr1  1  0.374  0.391  0.983  1.0
  Zr  Zr2  1  0.184  0.198  0.986  1.0
  Zr  Zr3  1  0.593  0.609  0.983  1.0
  Zr  Zr4  1  0.788  0.802  0.986  1.0
  O  O5  1  0.130  0.893  0.237  1.0
  O  O6  1  0.396  0.500  0.896  1.0
  O  O7  1  0.344  0.107  0.237  1.0
  O  O8  1  0.939  0.701  0.238  1.0
  O  O9  1  0.639  0.902  0.736  1.0
  O  O10  1  0.036  0.297  0.739  1.0
  O  O11  1  0.834  0.098  0.736  1.0
  O  O12  1  0.538  0.299  0.238  1.0
  O  O13  1  0.442  0.703  0.739  1.0
[/CIF]
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The crystal structure described by SmZr4O9 crystallizes in the orthorhombic Imm2 space group. Sm(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one O(2), one O(3), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of distorted edge and corner-sharing ZrO7 hexagonal pyramids. In the second Zr site, Zr(2) is bonded in a body-centered cubic geometry to one O(1), one O(4), three equivalent O(3), and three equivalent O(5) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Sm(1), one Zr(2), and two equivalent Zr(1) atoms to form OSmZr3 tetrahedra that share  a cornercorner with one O(5)Zr4 tetrahedra, corners with three equivalent O(1)SmZr3 tetrahedra, corners with three equivalent O(4)SmZr3 tetrahedra, corners with five equivalent O(3)Zr4 tetrahedra, edges with two equivalent O(4)SmZr3 tetrahedra, and edges with two equivalent O(5)Zr4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sm(1) and two equivalent Zr(1) atoms. In the third O site, O(3) is bonded to one Zr(1) and three equivalent Zr(2) atoms to form OZr4 tetrahedra that share  a cornercorner with one O(4)SmZr3 tetrahedra, corners with two equivalent O(5)Zr4 tetrahedra, corners with five equivalent O(1)SmZr3 tetrahedra, corners with six equivalent O(3)Zr4 tetrahedra, edges with two equivalent O(4)SmZr3 tetrahedra, and edges with four equivalent O(5)Zr4 tetrahedra. In the fourth O site, O(4) is bonded to one Sm(1), one Zr(2), and two equivalent Zr(1) atoms to form OSmZr3 tetrahedra that share  a cornercorner with one O(3)Zr4 tetrahedra, corners with three equivalent O(1)SmZr3 tetrahedra, corners with three equivalent O(4)SmZr3 tetrahedra, corners with five equivalent O(5)Zr4 tetrahedra, edges with two equivalent O(1)SmZr3 tetrahedra, and edges with two equivalent O(3)Zr4 tetrahedra. In the fifth O site, O(5) is bonded to one Zr(1) and three equivalent Zr(2) atoms to form OZr4 tetrahedra that share  a cornercorner with one O(1)SmZr3 tetrahedra, corners with two equivalent O(3)Zr4 tetrahedra, corners with five equivalent O(4)SmZr3 tetrahedra, corners with six equivalent O(5)Zr4 tetrahedra, edges with two equivalent O(1)SmZr3 tetrahedra, and edges with four equivalent O(3)Zr4 tetrahedra. is represented by the CIF file [CIF]
data_SmZr4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.944
_cell_length_b   9.944
_cell_length_c   9.944
_cell_angle_alpha   159.332
_cell_angle_beta   149.450
_cell_angle_gamma   37.171
_symmetry_Int_Tables_number   1
_cell_volume   176.185
_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
  Sm  Sm0  1  0.015  0.000  0.015  1.0
  Zr  Zr1  1  0.374  0.391  0.983  1.0
  Zr  Zr2  1  0.184  0.198  0.986  1.0
  Zr  Zr3  1  0.593  0.609  0.983  1.0
  Zr  Zr4  1  0.788  0.802  0.986  1.0
  O  O5  1  0.130  0.893  0.237  1.0
  O  O6  1  0.396  0.500  0.896  1.0
  O  O7  1  0.344  0.107  0.237  1.0
  O  O8  1  0.939  0.701  0.238  1.0
  O  O9  1  0.639  0.902  0.736  1.0
  O  O10  1  0.036  0.297  0.739  1.0
  O  O11  1  0.834  0.098  0.736  1.0
  O  O12  1  0.538  0.299  0.238  1.0
  O  O13  1  0.442  0.703  0.739  1.0
[/CIF]
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