The structure described by CaSmAl3O7 crystallizes in the orthorhombic Cmm2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Sm(1) is bonded in a 8-coordinate geometry to one O(2), one O(6), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(6), and two equivalent O(3) atoms to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(2), one O(5), and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded to two equivalent Ca(1) and two equivalent Al(3) atoms to form distorted OCa2Al2 tetrahedra that share corners with two equivalent O(2)Ca2SmAl tetrahedra, corners with two equivalent O(1)CaSm2Al tetrahedra, and edges with two equivalent O(2)Ca2SmAl tetrahedra. In the second O site, O(6) is bonded to two equivalent Sm(1) and two equivalent Al(2) atoms to form distorted OSm2Al2 tetrahedra that share corners with two equivalent O(2)Ca2SmAl tetrahedra, corners with two equivalent O(1)CaSm2Al tetrahedra, and edges with two equivalent O(1)CaSm2Al tetrahedra. In the third O site, O(1) is bonded to one Ca(1), two equivalent Sm(1), and one Al(2) atom to form distorted OCaSm2Al tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Sm2Al2 tetrahedra, corners with four equivalent O(2)Ca2SmAl tetrahedra,  an edgeedge with one O(1)CaSm2Al tetrahedra, and  an edgeedge with one O(6)Sm2Al2 tetrahedra. In the fourth O site, O(2) is bonded to two equivalent Ca(1), one Sm(1), and one Al(3) atom to form distorted OCa2SmAl tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Sm2Al2 tetrahedra, corners with four equivalent O(1)CaSm2Al tetrahedra,  an edgeedge with one O(5)Ca2Al2 tetrahedra, and  an edgeedge with one O(2)Ca2SmAl tetrahedra. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1), one Sm(1), one Al(1), and one Al(2) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(1), one Sm(1), one Al(1), and one Al(3) atom. is represented by the CIF card [CIF]
data_CaSmAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.800
_cell_length_b   7.800
_cell_length_c   5.141
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.511
_symmetry_Int_Tables_number   1
_cell_volume   312.733
_cell_formula_units_Z   2
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
  Ca  Ca0  1  0.660  0.660  0.483  1.0
  Ca  Ca1  1  0.340  0.340  0.483  1.0
  Sm  Sm2  1  0.837  0.163  0.512  1.0
  Sm  Sm3  1  0.163  0.837  0.512  1.0
  Al  Al4  1  0.500  0.000  0.003  1.0
  Al  Al5  1  0.000  0.500  0.003  1.0
  Al  Al6  1  0.856  0.856  0.041  1.0
  Al  Al7  1  0.643  0.357  0.957  1.0
  Al  Al8  1  0.144  0.144  0.041  1.0
  Al  Al9  1  0.357  0.643  0.957  1.0
  O  O10  1  0.866  0.866  0.702  1.0
  O  O11  1  0.648  0.352  0.295  1.0
  O  O12  1  0.134  0.134  0.702  1.0
  O  O13  1  0.352  0.648  0.295  1.0
  O  O14  1  0.663  0.914  0.200  1.0
  O  O15  1  0.842  0.405  0.801  1.0
  O  O16  1  0.337  0.086  0.200  1.0
  O  O17  1  0.158  0.595  0.801  1.0
  O  O18  1  0.405  0.842  0.801  1.0
  O  O19  1  0.086  0.337  0.200  1.0
  O  O20  1  0.595  0.158  0.801  1.0
  O  O21  1  0.914  0.663  0.200  1.0
  O  O22  1  0.500  0.500  0.813  1.0
  O  O23  1  0.000  0.000  0.196  1.0
[/CIF]
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The structure described by CaSmAl3O7 crystallizes in the orthorhombic Cmm2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Sm(1) is bonded in a 8-coordinate geometry to one O(2), one O(6), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(6), and two equivalent O(3) atoms to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(2), one O(5), and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded to two equivalent Ca(1) and two equivalent Al(3) atoms to form distorted OCa2Al2 tetrahedra that share corners with two equivalent O(2)Ca2SmAl tetrahedra, corners with two equivalent O(1)CaSm2Al tetrahedra, and edges with two equivalent O(2)Ca2SmAl tetrahedra. In the second O site, O(6) is bonded to two equivalent Sm(1) and two equivalent Al(2) atoms to form distorted OSm2Al2 tetrahedra that share corners with two equivalent O(2)Ca2SmAl tetrahedra, corners with two equivalent O(1)CaSm2Al tetrahedra, and edges with two equivalent O(1)CaSm2Al tetrahedra. In the third O site, O(1) is bonded to one Ca(1), two equivalent Sm(1), and one Al(2) atom to form distorted OCaSm2Al tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Sm2Al2 tetrahedra, corners with four equivalent O(2)Ca2SmAl tetrahedra,  an edgeedge with one O(1)CaSm2Al tetrahedra, and  an edgeedge with one O(6)Sm2Al2 tetrahedra. In the fourth O site, O(2) is bonded to two equivalent Ca(1), one Sm(1), and one Al(3) atom to form distorted OCa2SmAl tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Sm2Al2 tetrahedra, corners with four equivalent O(1)CaSm2Al tetrahedra,  an edgeedge with one O(5)Ca2Al2 tetrahedra, and  an edgeedge with one O(2)Ca2SmAl tetrahedra. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1), one Sm(1), one Al(1), and one Al(2) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(1), one Sm(1), one Al(1), and one Al(3) atom. is represented by the CIF card [CIF]
data_CaSmAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.800
_cell_length_b   7.800
_cell_length_c   5.141
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.511
_symmetry_Int_Tables_number   1
_cell_volume   312.733
_cell_formula_units_Z   2
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
  Ca  Ca0  1  0.660  0.660  0.483  1.0
  Ca  Ca1  1  0.340  0.340  0.483  1.0
  Sm  Sm2  1  0.837  0.163  0.512  1.0
  Sm  Sm3  1  0.163  0.837  0.512  1.0
  Al  Al4  1  0.500  0.000  0.003  1.0
  Al  Al5  1  0.000  0.500  0.003  1.0
  Al  Al6  1  0.856  0.856  0.041  1.0
  Al  Al7  1  0.643  0.357  0.957  1.0
  Al  Al8  1  0.144  0.144  0.041  1.0
  Al  Al9  1  0.357  0.643  0.957  1.0
  O  O10  1  0.866  0.866  0.702  1.0
  O  O11  1  0.648  0.352  0.295  1.0
  O  O12  1  0.134  0.134  0.702  1.0
  O  O13  1  0.352  0.648  0.295  1.0
  O  O14  1  0.663  0.914  0.200  1.0
  O  O15  1  0.842  0.405  0.801  1.0
  O  O16  1  0.337  0.086  0.200  1.0
  O  O17  1  0.158  0.595  0.801  1.0
  O  O18  1  0.405  0.842  0.801  1.0
  O  O19  1  0.086  0.337  0.200  1.0
  O  O20  1  0.595  0.158  0.801  1.0
  O  O21  1  0.914  0.663  0.200  1.0
  O  O22  1  0.500  0.500  0.813  1.0
  O  O23  1  0.000  0.000  0.196  1.0
[/CIF]
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