The material described by LaCaAl3O7 crystallizes in the monoclinic P2_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(5), two equivalent O(2), and two equivalent O(6) atoms. La(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(5), two equivalent O(3), and two equivalent O(7) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one La(1), one Al(1), and one Al(2) atom to form distorted OCaLaAl2 tetrahedra that share corners with two equivalent O(2)Ca2LaAl tetrahedra, corners with two equivalent O(3)CaLa2Al tetrahedra,  an edgeedge with one O(2)Ca2LaAl tetrahedra, and  an edgeedge with one O(3)CaLa2Al tetrahedra. In the second O site, O(2) is bonded to two equivalent Ca(1), one La(1), and one Al(1) atom to form distorted OCa2LaAl tetrahedra that share corners with two equivalent O(2)Ca2LaAl tetrahedra, corners with two equivalent O(3)CaLa2Al tetrahedra, corners with two equivalent O(1)CaLaAl2 tetrahedra,  an edgeedge with one O(3)CaLa2Al tetrahedra, and  an edgeedge with one O(1)CaLaAl2 tetrahedra. In the third O site, O(3) is bonded to one Ca(1), two equivalent La(1), and one Al(2) atom to form distorted OCaLa2Al tetrahedra that share corners with two equivalent O(2)Ca2LaAl tetrahedra, corners with two equivalent O(3)CaLa2Al tetrahedra, corners with two equivalent O(1)CaLaAl2 tetrahedra,  an edgeedge with one O(2)Ca2LaAl tetrahedra, and  an edgeedge with one O(1)CaLaAl2 tetrahedra. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ca(1), one La(1), one Al(2), and one Al(3) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(1), one La(1), one Al(1), and one Al(3) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ca(1), one Al(1), and one Al(3) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to two equivalent La(1), one Al(2), and one Al(3) atom. is represented by the CIF file [CIF]
data_CaLaAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.875
_cell_length_b   5.206
_cell_length_c   7.871
_cell_angle_alpha   89.244
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   322.691
_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  0.665  0.987  0.921  1.0
  Ca  Ca1  1  0.165  0.013  0.079  1.0
  La  La2  1  0.340  0.987  0.595  1.0
  La  La3  1  0.840  0.013  0.405  1.0
  Al  Al4  1  0.857  0.542  0.103  1.0
  Al  Al5  1  0.357  0.458  0.897  1.0
  Al  Al6  1  0.144  0.539  0.390  1.0
  Al  Al7  1  0.644  0.461  0.610  1.0
  Al  Al8  1  0.501  0.500  0.251  1.0
  Al  Al9  1  0.001  0.500  0.749  1.0
  O  O10  1  0.505  0.316  0.757  1.0
  O  O11  1  0.005  0.684  0.243  1.0
  O  O12  1  0.855  0.205  0.116  1.0
  O  O13  1  0.355  0.795  0.884  1.0
  O  O14  1  0.137  0.202  0.398  1.0
  O  O15  1  0.637  0.798  0.602  1.0
  O  O16  1  0.841  0.310  0.653  1.0
  O  O17  1  0.341  0.690  0.347  1.0
  O  O18  1  0.164  0.303  0.835  1.0
  O  O19  1  0.664  0.697  0.165  1.0
  O  O20  1  0.905  0.691  0.906  1.0
  O  O21  1  0.405  0.309  0.094  1.0
  O  O22  1  0.087  0.695  0.583  1.0
  O  O23  1  0.587  0.305  0.417  1.0
[/CIF]
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The material described by LaCaAl3O7 crystallizes in the monoclinic P2_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(5), two equivalent O(2), and two equivalent O(6) atoms. La(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(5), two equivalent O(3), and two equivalent O(7) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one La(1), one Al(1), and one Al(2) atom to form distorted OCaLaAl2 tetrahedra that share corners with two equivalent O(2)Ca2LaAl tetrahedra, corners with two equivalent O(3)CaLa2Al tetrahedra,  an edgeedge with one O(2)Ca2LaAl tetrahedra, and  an edgeedge with one O(3)CaLa2Al tetrahedra. In the second O site, O(2) is bonded to two equivalent Ca(1), one La(1), and one Al(1) atom to form distorted OCa2LaAl tetrahedra that share corners with two equivalent O(2)Ca2LaAl tetrahedra, corners with two equivalent O(3)CaLa2Al tetrahedra, corners with two equivalent O(1)CaLaAl2 tetrahedra,  an edgeedge with one O(3)CaLa2Al tetrahedra, and  an edgeedge with one O(1)CaLaAl2 tetrahedra. In the third O site, O(3) is bonded to one Ca(1), two equivalent La(1), and one Al(2) atom to form distorted OCaLa2Al tetrahedra that share corners with two equivalent O(2)Ca2LaAl tetrahedra, corners with two equivalent O(3)CaLa2Al tetrahedra, corners with two equivalent O(1)CaLaAl2 tetrahedra,  an edgeedge with one O(2)Ca2LaAl tetrahedra, and  an edgeedge with one O(1)CaLaAl2 tetrahedra. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ca(1), one La(1), one Al(2), and one Al(3) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(1), one La(1), one Al(1), and one Al(3) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ca(1), one Al(1), and one Al(3) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to two equivalent La(1), one Al(2), and one Al(3) atom. is represented by the CIF file [CIF]
data_CaLaAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.875
_cell_length_b   5.206
_cell_length_c   7.871
_cell_angle_alpha   89.244
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   322.691
_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  0.665  0.987  0.921  1.0
  Ca  Ca1  1  0.165  0.013  0.079  1.0
  La  La2  1  0.340  0.987  0.595  1.0
  La  La3  1  0.840  0.013  0.405  1.0
  Al  Al4  1  0.857  0.542  0.103  1.0
  Al  Al5  1  0.357  0.458  0.897  1.0
  Al  Al6  1  0.144  0.539  0.390  1.0
  Al  Al7  1  0.644  0.461  0.610  1.0
  Al  Al8  1  0.501  0.500  0.251  1.0
  Al  Al9  1  0.001  0.500  0.749  1.0
  O  O10  1  0.505  0.316  0.757  1.0
  O  O11  1  0.005  0.684  0.243  1.0
  O  O12  1  0.855  0.205  0.116  1.0
  O  O13  1  0.355  0.795  0.884  1.0
  O  O14  1  0.137  0.202  0.398  1.0
  O  O15  1  0.637  0.798  0.602  1.0
  O  O16  1  0.841  0.310  0.653  1.0
  O  O17  1  0.341  0.690  0.347  1.0
  O  O18  1  0.164  0.303  0.835  1.0
  O  O19  1  0.664  0.697  0.165  1.0
  O  O20  1  0.905  0.691  0.906  1.0
  O  O21  1  0.405  0.309  0.094  1.0
  O  O22  1  0.087  0.695  0.583  1.0
  O  O23  1  0.587  0.305  0.417  1.0
[/CIF]
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