The material structure described by La1.0Ca2.0Mn2O7 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to two equivalent O(3), three equivalent O(2), and four equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(3), and four equivalent O(4) atoms. La(1) is bonded to four equivalent O(1) and eight equivalent O(4) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(1)O12 cuboctahedra, faces with four equivalent La(1)O12 cuboctahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with four equivalent Mn(2)O6 octahedra. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form MnO6 octahedra that share corners with five equivalent Mn(2)O6 octahedra and faces with four equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the second Mn site, Mn(2) is bonded to one O(1), one O(3), and four equivalent O(4) atoms to form MnO6 octahedra that share corners with five equivalent Mn(1)O6 octahedra and faces with four equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent La(1), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Mn(1) atom to form distorted OCa5Mn octahedra that share corners with four equivalent O(2)Ca5Mn octahedra, corners with twelve equivalent O(4)Ca2La2Mn2 octahedra, edges with two equivalent O(2)Ca5Mn octahedra, edges with six equivalent O(3)Ca5Mn octahedra, and faces with four equivalent O(4)Ca2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 12-52°. In the third O site, O(3) is bonded to two equivalent Ca(1), three equivalent Ca(2), and one Mn(2) atom to form distorted OCa5Mn octahedra that share corners with four equivalent O(3)Ca5Mn octahedra, corners with twelve equivalent O(4)Ca2La2Mn2 octahedra, edges with two equivalent O(3)Ca5Mn octahedra, edges with six equivalent O(2)Ca5Mn octahedra, and faces with four equivalent O(4)Ca2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 12-55°. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), two equivalent La(1), one Mn(1), and one Mn(2) atom to form distorted OCa2La2Mn2 octahedra that share corners with three equivalent O(2)Ca5Mn octahedra, corners with three equivalent O(3)Ca5Mn octahedra, corners with eight equivalent O(4)Ca2La2Mn2 octahedra, edges with three equivalent O(4)Ca2La2Mn2 octahedra,  a faceface with one O(2)Ca5Mn octahedra,  a faceface with one O(3)Ca5Mn octahedra, and faces with four equivalent O(4)Ca2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 3-62°. is represented by the CIF card [CIF]
data_Ca2LaMn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.895
_cell_length_b   3.895
_cell_length_c   10.063
_cell_angle_alpha   101.159
_cell_angle_beta   101.159
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   146.842
_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
  Ca  Ca0  1  0.685  0.685  0.369  1.0
  Ca  Ca1  1  0.315  0.315  0.631  1.0
  La  La2  1  0.500  0.500  1.000  1.0
  Mn  Mn3  1  0.898  0.898  0.795  1.0
  Mn  Mn4  1  0.102  0.102  0.205  1.0
  O  O5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.800  0.800  0.601  1.0
  O  O7  1  0.200  0.200  0.399  1.0
  O  O8  1  0.904  0.404  0.808  1.0
  O  O9  1  0.096  0.596  0.192  1.0
  O  O10  1  0.404  0.904  0.808  1.0
  O  O11  1  0.596  0.096  0.192  1.0
[/CIF]
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The material structure described by La1.0Ca2.0Mn2O7 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to two equivalent O(3), three equivalent O(2), and four equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(3), and four equivalent O(4) atoms. La(1) is bonded to four equivalent O(1) and eight equivalent O(4) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(1)O12 cuboctahedra, faces with four equivalent La(1)O12 cuboctahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with four equivalent Mn(2)O6 octahedra. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form MnO6 octahedra that share corners with five equivalent Mn(2)O6 octahedra and faces with four equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the second Mn site, Mn(2) is bonded to one O(1), one O(3), and four equivalent O(4) atoms to form MnO6 octahedra that share corners with five equivalent Mn(1)O6 octahedra and faces with four equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent La(1), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Mn(1) atom to form distorted OCa5Mn octahedra that share corners with four equivalent O(2)Ca5Mn octahedra, corners with twelve equivalent O(4)Ca2La2Mn2 octahedra, edges with two equivalent O(2)Ca5Mn octahedra, edges with six equivalent O(3)Ca5Mn octahedra, and faces with four equivalent O(4)Ca2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 12-52°. In the third O site, O(3) is bonded to two equivalent Ca(1), three equivalent Ca(2), and one Mn(2) atom to form distorted OCa5Mn octahedra that share corners with four equivalent O(3)Ca5Mn octahedra, corners with twelve equivalent O(4)Ca2La2Mn2 octahedra, edges with two equivalent O(3)Ca5Mn octahedra, edges with six equivalent O(2)Ca5Mn octahedra, and faces with four equivalent O(4)Ca2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 12-55°. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), two equivalent La(1), one Mn(1), and one Mn(2) atom to form distorted OCa2La2Mn2 octahedra that share corners with three equivalent O(2)Ca5Mn octahedra, corners with three equivalent O(3)Ca5Mn octahedra, corners with eight equivalent O(4)Ca2La2Mn2 octahedra, edges with three equivalent O(4)Ca2La2Mn2 octahedra,  a faceface with one O(2)Ca5Mn octahedra,  a faceface with one O(3)Ca5Mn octahedra, and faces with four equivalent O(4)Ca2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 3-62°. is represented by the CIF card [CIF]
data_Ca2LaMn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.895
_cell_length_b   3.895
_cell_length_c   10.063
_cell_angle_alpha   101.159
_cell_angle_beta   101.159
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   146.842
_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
  Ca  Ca0  1  0.685  0.685  0.369  1.0
  Ca  Ca1  1  0.315  0.315  0.631  1.0
  La  La2  1  0.500  0.500  1.000  1.0
  Mn  Mn3  1  0.898  0.898  0.795  1.0
  Mn  Mn4  1  0.102  0.102  0.205  1.0
  O  O5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.800  0.800  0.601  1.0
  O  O7  1  0.200  0.200  0.399  1.0
  O  O8  1  0.904  0.404  0.808  1.0
  O  O9  1  0.096  0.596  0.192  1.0
  O  O10  1  0.404  0.904  0.808  1.0
  O  O11  1  0.596  0.096  0.192  1.0
[/CIF]
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