The structure described by Sm2CuAs3O crystallizes in the orthorhombic Pnma space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), and four equivalent O(1) atoms. In the second Sm site, Sm(2) is bonded to four equivalent Cu(1), two equivalent As(1), two equivalent As(2), and four equivalent As(3) atoms to form distorted SmCu4As8 cuboctahedra that share corners with four equivalent Sm(2)Cu4As8 cuboctahedra, corners with eight equivalent Cu(1)Sm4As4 tetrahedra, edges with four equivalent Sm(2)Cu4As8 cuboctahedra, edges with four equivalent Cu(1)Sm4As4 tetrahedra, and faces with four equivalent Sm(2)Cu4As8 cuboctahedra. Cu(1) is bonded to four equivalent Sm(2) and four equivalent As(3) atoms to form distorted CuSm4As4 tetrahedra that share corners with eight equivalent Sm(2)Cu4As8 cuboctahedra, edges with four equivalent Sm(2)Cu4As8 cuboctahedra, edges with four equivalent Cu(1)Sm4As4 tetrahedra, and faces with four equivalent Cu(1)Sm4As4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 6-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), and four equivalent As(2) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), and four equivalent As(1) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to four equivalent Sm(2) and four equivalent Cu(1) atoms. O(1) is bonded to four equivalent Sm(1) atoms to form a mixture of edge and corner-sharing OSm4 tetrahedra. is represented by the CIF card [CIF]
data_Sm2CuAs3O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.991
_cell_length_b   4.000
_cell_length_c   34.823
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   555.899
_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
  Sm  Sm0  1  0.750  0.751  0.967  1.0
  Sm  Sm1  1  0.250  0.251  0.533  1.0
  Sm  Sm2  1  0.750  0.749  0.467  1.0
  Sm  Sm3  1  0.250  0.249  0.033  1.0
  Sm  Sm4  1  0.250  0.308  0.824  1.0
  Sm  Sm5  1  0.750  0.808  0.676  1.0
  Sm  Sm6  1  0.250  0.192  0.324  1.0
  Sm  Sm7  1  0.750  0.692  0.176  1.0
  Cu  Cu8  1  0.250  0.808  0.750  1.0
  Cu  Cu9  1  0.750  0.308  0.750  1.0
  Cu  Cu10  1  0.250  0.692  0.250  1.0
  Cu  Cu11  1  0.750  0.192  0.250  1.0
  As  As12  1  0.250  0.831  0.893  1.0
  As  As13  1  0.750  0.331  0.607  1.0
  As  As14  1  0.250  0.669  0.393  1.0
  As  As15  1  0.750  0.169  0.107  1.0
  As  As16  1  0.750  0.251  0.894  1.0
  As  As17  1  0.250  0.751  0.606  1.0
  As  As18  1  0.750  0.249  0.394  1.0
  As  As19  1  0.250  0.749  0.106  1.0
  As  As20  1  0.250  0.309  0.705  1.0
  As  As21  1  0.750  0.809  0.795  1.0
  As  As22  1  0.250  0.191  0.205  1.0
  As  As23  1  0.750  0.691  0.295  1.0
  O  O24  1  0.750  0.251  0.000  1.0
  O  O25  1  0.250  0.751  0.500  1.0
  O  O26  1  0.750  0.249  0.500  1.0
  O  O27  1  0.250  0.749  1.000  1.0
[/CIF]
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The structure described by Sm2CuAs3O crystallizes in the orthorhombic Pnma space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), and four equivalent O(1) atoms. In the second Sm site, Sm(2) is bonded to four equivalent Cu(1), two equivalent As(1), two equivalent As(2), and four equivalent As(3) atoms to form distorted SmCu4As8 cuboctahedra that share corners with four equivalent Sm(2)Cu4As8 cuboctahedra, corners with eight equivalent Cu(1)Sm4As4 tetrahedra, edges with four equivalent Sm(2)Cu4As8 cuboctahedra, edges with four equivalent Cu(1)Sm4As4 tetrahedra, and faces with four equivalent Sm(2)Cu4As8 cuboctahedra. Cu(1) is bonded to four equivalent Sm(2) and four equivalent As(3) atoms to form distorted CuSm4As4 tetrahedra that share corners with eight equivalent Sm(2)Cu4As8 cuboctahedra, edges with four equivalent Sm(2)Cu4As8 cuboctahedra, edges with four equivalent Cu(1)Sm4As4 tetrahedra, and faces with four equivalent Cu(1)Sm4As4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 6-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), and four equivalent As(2) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), and four equivalent As(1) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to four equivalent Sm(2) and four equivalent Cu(1) atoms. O(1) is bonded to four equivalent Sm(1) atoms to form a mixture of edge and corner-sharing OSm4 tetrahedra. is represented by the CIF card [CIF]
data_Sm2CuAs3O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.991
_cell_length_b   4.000
_cell_length_c   34.823
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   555.899
_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
  Sm  Sm0  1  0.750  0.751  0.967  1.0
  Sm  Sm1  1  0.250  0.251  0.533  1.0
  Sm  Sm2  1  0.750  0.749  0.467  1.0
  Sm  Sm3  1  0.250  0.249  0.033  1.0
  Sm  Sm4  1  0.250  0.308  0.824  1.0
  Sm  Sm5  1  0.750  0.808  0.676  1.0
  Sm  Sm6  1  0.250  0.192  0.324  1.0
  Sm  Sm7  1  0.750  0.692  0.176  1.0
  Cu  Cu8  1  0.250  0.808  0.750  1.0
  Cu  Cu9  1  0.750  0.308  0.750  1.0
  Cu  Cu10  1  0.250  0.692  0.250  1.0
  Cu  Cu11  1  0.750  0.192  0.250  1.0
  As  As12  1  0.250  0.831  0.893  1.0
  As  As13  1  0.750  0.331  0.607  1.0
  As  As14  1  0.250  0.669  0.393  1.0
  As  As15  1  0.750  0.169  0.107  1.0
  As  As16  1  0.750  0.251  0.894  1.0
  As  As17  1  0.250  0.751  0.606  1.0
  As  As18  1  0.750  0.249  0.394  1.0
  As  As19  1  0.250  0.749  0.106  1.0
  As  As20  1  0.250  0.309  0.705  1.0
  As  As21  1  0.750  0.809  0.795  1.0
  As  As22  1  0.250  0.191  0.205  1.0
  As  As23  1  0.750  0.691  0.295  1.0
  O  O24  1  0.750  0.251  0.000  1.0
  O  O25  1  0.250  0.751  0.500  1.0
  O  O26  1  0.750  0.249  0.500  1.0
  O  O27  1  0.250  0.749  1.000  1.0
[/CIF]
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