The material structure described by SmCe9O20 is Fluorite-derived structured and crystallizes in the triclinic P-1 space group. Sm(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(8), and two equivalent O(9) atoms. There are five inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a body-centered cubic geometry to one O(5), one O(7), one O(8), one O(9), two equivalent O(1), and two equivalent O(4) atoms. In the second Ce site, Ce(2) is bonded in a body-centered cubic geometry to one O(1), one O(10), one O(4), one O(6), one O(8), one O(9), and two equivalent O(2) atoms. In the third Ce site, Ce(3) is bonded in a body-centered cubic geometry to two equivalent O(3), two equivalent O(6), two equivalent O(7), and two equivalent O(9) atoms. In the fourth Ce site, Ce(4) is bonded in a body-centered cubic geometry to one O(1), one O(3), one O(7), one O(8), two equivalent O(10), and two equivalent O(5) atoms. In the fifth Ce site, Ce(5) is bonded in a body-centered cubic geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(7), and two equivalent O(6) atoms. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Ce(2), one Ce(4), and two equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(5)Ce4 tetrahedra, corners with three equivalent O(4)Ce4 tetrahedra, corners with four equivalent O(8)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the second O site, O(2) is bonded to one Sm(1), one Ce(5), and two equivalent Ce(2) atoms to form OCe3Sm tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(8)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with three equivalent O(4)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra, and  an edgeedge with one O(6)Ce4 tetrahedra. In the third O site, O(3) is bonded to one Sm(1), one Ce(3), one Ce(4), and one Ce(5) atom to form OCe3Sm tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with two equivalent O(7)Ce4 tetrahedra, corners with three equivalent O(10)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the fourth O site, O(4) is bonded to one Ce(2), one Ce(5), and two equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(10)Ce4 tetrahedra, corners with three equivalent O(2)Ce3Sm tetrahedra, corners with three equivalent O(9)Ce3Sm tetrahedra, corners with three equivalent O(1)Ce4 tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the fifth O site, O(5) is bonded to one Ce(1), one Ce(5), and two equivalent Ce(4) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with three equivalent O(10)Ce4 tetrahedra, corners with four equivalent O(7)Ce4 tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra, and  an edgeedge with one O(5)Ce4 tetrahedra. In the sixth O site, O(6) is bonded to one Ce(2), one Ce(3), and two equivalent Ce(5) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(5)Ce4 tetrahedra, corners with two equivalent O(7)Ce4 tetrahedra, corners with three equivalent O(10)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the seventh O site, O(7) is bonded to one Ce(1), one Ce(3), one Ce(4), and one Ce(5) atom to form OCe4 tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(8)Ce3Sm tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with four equivalent O(5)Ce4 tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra, and  an edgeedge with one O(6)Ce4 tetrahedra. In the eighth O site, O(8) is bonded to one Sm(1), one Ce(1), one Ce(2), and one Ce(4) atom to form OCe3Sm tetrahedra that share  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with two equivalent O(7)Ce4 tetrahedra, corners with four equivalent O(1)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra, and  an edgeedge with one O(5)Ce4 tetrahedra. In the ninth O site, O(9) is bonded to one Sm(1), one Ce(1), one Ce(2), and one Ce(3) atom to form OCe3Sm tetrahedra that share  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(8)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with three equivalent O(4)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the tenth O site, O(10) is bonded to one Ce(2), one Ce(5), and two equivalent Ce(4) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with three equivalent O(3)Ce3Sm tetrahedra, corners with three equivalent O(5)Ce4 tetrahedra, corners with three equivalent O(6)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce9SmO20
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.667
_cell_length_b   7.697
_cell_length_c   8.607
_cell_angle_alpha   102.928
_cell_angle_beta   97.420
_cell_angle_gamma   106.769
_symmetry_Int_Tables_number   1
_cell_volume   403.167
_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
  Ce  Ce0  1  0.800  0.601  0.601  1.0
  Ce  Ce1  1  0.600  0.200  0.199  1.0
  Ce  Ce2  1  0.000  0.500  0.000  1.0
  Ce  Ce3  1  0.800  0.100  0.601  1.0
  Ce  Ce4  1  0.400  0.800  0.801  1.0
  Ce  Ce5  1  0.200  0.399  0.399  1.0
  Ce  Ce6  1  0.602  0.701  0.200  1.0
  Ce  Ce7  1  0.398  0.299  0.800  1.0
  Ce  Ce8  1  0.200  0.900  0.399  1.0
  Sm  Sm9  1  0.000  0.000  0.000  1.0
  O  O10  1  0.850  0.325  0.452  1.0
  O  O11  1  0.643  0.923  0.052  1.0
  O  O12  1  0.950  0.770  0.153  1.0
  O  O13  1  0.448  0.523  0.649  1.0
  O  O14  1  0.852  0.826  0.451  1.0
  O  O15  1  0.648  0.425  0.049  1.0
  O  O16  1  0.746  0.374  0.750  1.0
  O  O17  1  0.256  0.128  0.255  1.0
  O  O18  1  0.949  0.281  0.154  1.0
  O  O19  1  0.448  0.025  0.649  1.0
  O  O20  1  0.552  0.975  0.351  1.0
  O  O21  1  0.051  0.719  0.846  1.0
  O  O22  1  0.744  0.872  0.745  1.0
  O  O23  1  0.352  0.575  0.951  1.0
  O  O24  1  0.254  0.626  0.250  1.0
  O  O25  1  0.552  0.477  0.351  1.0
  O  O26  1  0.148  0.174  0.549  1.0
  O  O27  1  0.050  0.230  0.847  1.0
  O  O28  1  0.357  0.077  0.948  1.0
  O  O29  1  0.150  0.675  0.548  1.0
[/CIF]
.
The material structure described by SmCe9O20 is Fluorite-derived structured and crystallizes in the triclinic P-1 space group. Sm(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(8), and two equivalent O(9) atoms. There are five inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a body-centered cubic geometry to one O(5), one O(7), one O(8), one O(9), two equivalent O(1), and two equivalent O(4) atoms. In the second Ce site, Ce(2) is bonded in a body-centered cubic geometry to one O(1), one O(10), one O(4), one O(6), one O(8), one O(9), and two equivalent O(2) atoms. In the third Ce site, Ce(3) is bonded in a body-centered cubic geometry to two equivalent O(3), two equivalent O(6), two equivalent O(7), and two equivalent O(9) atoms. In the fourth Ce site, Ce(4) is bonded in a body-centered cubic geometry to one O(1), one O(3), one O(7), one O(8), two equivalent O(10), and two equivalent O(5) atoms. In the fifth Ce site, Ce(5) is bonded in a body-centered cubic geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(7), and two equivalent O(6) atoms. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Ce(2), one Ce(4), and two equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(5)Ce4 tetrahedra, corners with three equivalent O(4)Ce4 tetrahedra, corners with four equivalent O(8)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the second O site, O(2) is bonded to one Sm(1), one Ce(5), and two equivalent Ce(2) atoms to form OCe3Sm tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(8)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with three equivalent O(4)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra, and  an edgeedge with one O(6)Ce4 tetrahedra. In the third O site, O(3) is bonded to one Sm(1), one Ce(3), one Ce(4), and one Ce(5) atom to form OCe3Sm tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with two equivalent O(7)Ce4 tetrahedra, corners with three equivalent O(10)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the fourth O site, O(4) is bonded to one Ce(2), one Ce(5), and two equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(10)Ce4 tetrahedra, corners with three equivalent O(2)Ce3Sm tetrahedra, corners with three equivalent O(9)Ce3Sm tetrahedra, corners with three equivalent O(1)Ce4 tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the fifth O site, O(5) is bonded to one Ce(1), one Ce(5), and two equivalent Ce(4) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with three equivalent O(10)Ce4 tetrahedra, corners with four equivalent O(7)Ce4 tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra, and  an edgeedge with one O(5)Ce4 tetrahedra. In the sixth O site, O(6) is bonded to one Ce(2), one Ce(3), and two equivalent Ce(5) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(5)Ce4 tetrahedra, corners with two equivalent O(7)Ce4 tetrahedra, corners with three equivalent O(10)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the seventh O site, O(7) is bonded to one Ce(1), one Ce(3), one Ce(4), and one Ce(5) atom to form OCe4 tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(8)Ce3Sm tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with four equivalent O(5)Ce4 tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra, and  an edgeedge with one O(6)Ce4 tetrahedra. In the eighth O site, O(8) is bonded to one Sm(1), one Ce(1), one Ce(2), and one Ce(4) atom to form OCe3Sm tetrahedra that share  a cornercorner with one O(3)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with two equivalent O(7)Ce4 tetrahedra, corners with four equivalent O(1)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(9)Ce3Sm tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra, and  an edgeedge with one O(5)Ce4 tetrahedra. In the ninth O site, O(9) is bonded to one Sm(1), one Ce(1), one Ce(2), and one Ce(3) atom to form OCe3Sm tetrahedra that share  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(10)Ce4 tetrahedra,  a cornercorner with one O(5)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(2)Ce3Sm tetrahedra, corners with two equivalent O(3)Ce3Sm tetrahedra, corners with two equivalent O(8)Ce3Sm tetrahedra, corners with two equivalent O(9)Ce3Sm tetrahedra, corners with three equivalent O(4)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(3)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(6)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. In the tenth O site, O(10) is bonded to one Ce(2), one Ce(5), and two equivalent Ce(4) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(2)Ce3Sm tetrahedra,  a cornercorner with one O(8)Ce3Sm tetrahedra,  a cornercorner with one O(9)Ce3Sm tetrahedra,  a cornercorner with one O(1)Ce4 tetrahedra,  a cornercorner with one O(7)Ce4 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with three equivalent O(3)Ce3Sm tetrahedra, corners with three equivalent O(5)Ce4 tetrahedra, corners with three equivalent O(6)Ce4 tetrahedra,  an edgeedge with one O(2)Ce3Sm tetrahedra,  an edgeedge with one O(8)Ce3Sm tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(10)Ce4 tetrahedra,  an edgeedge with one O(5)Ce4 tetrahedra, and  an edgeedge with one O(7)Ce4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce9SmO20
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.667
_cell_length_b   7.697
_cell_length_c   8.607
_cell_angle_alpha   102.928
_cell_angle_beta   97.420
_cell_angle_gamma   106.769
_symmetry_Int_Tables_number   1
_cell_volume   403.167
_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
  Ce  Ce0  1  0.800  0.601  0.601  1.0
  Ce  Ce1  1  0.600  0.200  0.199  1.0
  Ce  Ce2  1  0.000  0.500  0.000  1.0
  Ce  Ce3  1  0.800  0.100  0.601  1.0
  Ce  Ce4  1  0.400  0.800  0.801  1.0
  Ce  Ce5  1  0.200  0.399  0.399  1.0
  Ce  Ce6  1  0.602  0.701  0.200  1.0
  Ce  Ce7  1  0.398  0.299  0.800  1.0
  Ce  Ce8  1  0.200  0.900  0.399  1.0
  Sm  Sm9  1  0.000  0.000  0.000  1.0
  O  O10  1  0.850  0.325  0.452  1.0
  O  O11  1  0.643  0.923  0.052  1.0
  O  O12  1  0.950  0.770  0.153  1.0
  O  O13  1  0.448  0.523  0.649  1.0
  O  O14  1  0.852  0.826  0.451  1.0
  O  O15  1  0.648  0.425  0.049  1.0
  O  O16  1  0.746  0.374  0.750  1.0
  O  O17  1  0.256  0.128  0.255  1.0
  O  O18  1  0.949  0.281  0.154  1.0
  O  O19  1  0.448  0.025  0.649  1.0
  O  O20  1  0.552  0.975  0.351  1.0
  O  O21  1  0.051  0.719  0.846  1.0
  O  O22  1  0.744  0.872  0.745  1.0
  O  O23  1  0.352  0.575  0.951  1.0
  O  O24  1  0.254  0.626  0.250  1.0
  O  O25  1  0.552  0.477  0.351  1.0
  O  O26  1  0.148  0.174  0.549  1.0
  O  O27  1  0.050  0.230  0.847  1.0
  O  O28  1  0.357  0.077  0.948  1.0
  O  O29  1  0.150  0.675  0.548  1.0
[/CIF]
.