The material structure described by LaSr2Mn2O7 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(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 Sr site, Sr(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 0-8°. 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 0-8°. 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 Sr(2), three equivalent Sr(1), and one Mn(1) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(2)Sr5Mn octahedra, corners with twelve equivalent O(4)Sr2La2Mn2 octahedra, edges with two equivalent O(2)Sr5Mn octahedra, edges with six equivalent O(3)Sr5Mn octahedra, and faces with four equivalent O(4)Sr2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 8-54°. In the third O site, O(3) is bonded to two equivalent Sr(1), three equivalent Sr(2), and one Mn(2) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(3)Sr5Mn octahedra, corners with twelve equivalent O(4)Sr2La2Mn2 octahedra, edges with two equivalent O(3)Sr5Mn octahedra, edges with six equivalent O(2)Sr5Mn octahedra, and faces with four equivalent O(4)Sr2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 9-57°. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(2), two equivalent La(1), one Mn(1), and one Mn(2) atom to form distorted OSr2La2Mn2 octahedra that share corners with three equivalent O(2)Sr5Mn octahedra, corners with three equivalent O(3)Sr5Mn octahedra, corners with eight equivalent O(4)Sr2La2Mn2 octahedra, edges with three equivalent O(4)Sr2La2Mn2 octahedra,  a faceface with one O(2)Sr5Mn octahedra,  a faceface with one O(3)Sr5Mn octahedra, and faces with four equivalent O(4)Sr2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 3-62°. is represented by the CIF file [CIF]
data_Sr2LaMn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.937
_cell_length_b   3.937
_cell_length_c   10.398
_cell_angle_alpha   100.911
_cell_angle_beta   100.911
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   155.248
_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
  La  La0  1  0.500  0.500  0.000  1.0
  Mn  Mn1  1  0.098  0.098  0.196  1.0
  Mn  Mn2  1  0.902  0.902  0.804  1.0
  O  O3  1  1.000  1.000  1.000  1.0
  O  O4  1  0.194  0.194  0.387  1.0
  O  O5  1  0.806  0.806  0.613  1.0
  O  O6  1  0.591  0.091  0.183  1.0
  O  O7  1  0.091  0.591  0.183  1.0
  O  O8  1  0.409  0.909  0.817  1.0
  O  O9  1  0.909  0.409  0.817  1.0
  Sr  Sr10  1  0.317  0.317  0.634  1.0
  Sr  Sr11  1  0.683  0.683  0.366  1.0
[/CIF]
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The material structure described by LaSr2Mn2O7 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(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 Sr site, Sr(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 0-8°. 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 0-8°. 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 Sr(2), three equivalent Sr(1), and one Mn(1) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(2)Sr5Mn octahedra, corners with twelve equivalent O(4)Sr2La2Mn2 octahedra, edges with two equivalent O(2)Sr5Mn octahedra, edges with six equivalent O(3)Sr5Mn octahedra, and faces with four equivalent O(4)Sr2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 8-54°. In the third O site, O(3) is bonded to two equivalent Sr(1), three equivalent Sr(2), and one Mn(2) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(3)Sr5Mn octahedra, corners with twelve equivalent O(4)Sr2La2Mn2 octahedra, edges with two equivalent O(3)Sr5Mn octahedra, edges with six equivalent O(2)Sr5Mn octahedra, and faces with four equivalent O(4)Sr2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 9-57°. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(2), two equivalent La(1), one Mn(1), and one Mn(2) atom to form distorted OSr2La2Mn2 octahedra that share corners with three equivalent O(2)Sr5Mn octahedra, corners with three equivalent O(3)Sr5Mn octahedra, corners with eight equivalent O(4)Sr2La2Mn2 octahedra, edges with three equivalent O(4)Sr2La2Mn2 octahedra,  a faceface with one O(2)Sr5Mn octahedra,  a faceface with one O(3)Sr5Mn octahedra, and faces with four equivalent O(4)Sr2La2Mn2 octahedra. The corner-sharing octahedral tilt angles range from 3-62°. is represented by the CIF file [CIF]
data_Sr2LaMn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.937
_cell_length_b   3.937
_cell_length_c   10.398
_cell_angle_alpha   100.911
_cell_angle_beta   100.911
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   155.248
_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
  La  La0  1  0.500  0.500  0.000  1.0
  Mn  Mn1  1  0.098  0.098  0.196  1.0
  Mn  Mn2  1  0.902  0.902  0.804  1.0
  O  O3  1  1.000  1.000  1.000  1.0
  O  O4  1  0.194  0.194  0.387  1.0
  O  O5  1  0.806  0.806  0.613  1.0
  O  O6  1  0.591  0.091  0.183  1.0
  O  O7  1  0.091  0.591  0.183  1.0
  O  O8  1  0.409  0.909  0.817  1.0
  O  O9  1  0.909  0.409  0.817  1.0
  Sr  Sr10  1  0.317  0.317  0.634  1.0
  Sr  Sr11  1  0.683  0.683  0.366  1.0
[/CIF]
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