The crystal structure described by SrEu3(NiO4)2 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(5) atoms. There are three inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(5) atoms. In the second Eu site, Eu(2) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and four equivalent O(5) atoms. In the third Eu site, Eu(3) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and four equivalent O(5) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(4), and four equivalent O(5) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Ni site, Ni(2) is bonded to one O(2), one O(3), and four equivalent O(5) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Eu(1), two equivalent Eu(2), two equivalent Eu(3), and one Ni(1) atom to form distorted OEu5Ni octahedra that share  a cornercorner with one O(4)Sr2Eu3Ni octahedra, corners with four equivalent O(1)Eu5Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(3)Sr2Eu3Ni octahedra, edges with two equivalent O(4)Sr2Eu3Ni octahedra, edges with four equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-52°. In the second O site, O(2) is bonded to one Sr(1), two equivalent Eu(2), two equivalent Eu(3), and one Ni(2) atom to form distorted OSrEu4Ni octahedra that share  a cornercorner with one O(3)Sr2Eu3Ni octahedra, corners with four equivalent O(2)SrEu4Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(3)Sr2Eu3Ni octahedra, edges with two equivalent O(4)Sr2Eu3Ni octahedra, edges with four equivalent O(1)Eu5Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-54°. In the third O site, O(3) is bonded to two equivalent Sr(1), one Eu(3), two equivalent Eu(1), and one Ni(2) atom to form distorted OSr2Eu3Ni octahedra that share  a cornercorner with one O(2)SrEu4Ni octahedra, corners with four equivalent O(3)Sr2Eu3Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(1)Eu5Ni octahedra, edges with two equivalent O(2)SrEu4Ni octahedra, edges with four equivalent O(4)Sr2Eu3Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the fourth O site, O(4) is bonded to two equivalent Sr(1), one Eu(2), two equivalent Eu(1), and one Ni(1) atom to form distorted OSr2Eu3Ni octahedra that share  a cornercorner with one O(1)Eu5Ni octahedra, corners with four equivalent O(4)Sr2Eu3Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(1)Eu5Ni octahedra, edges with two equivalent O(2)SrEu4Ni octahedra, edges with four equivalent O(3)Sr2Eu3Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the fifth O site, O(5) is bonded to one Sr(1), one Eu(1), one Eu(2), one Eu(3), one Ni(1), and one Ni(2) atom to form distorted OSrEu3Ni2 octahedra that share corners with two equivalent O(5)SrEu3Ni2 octahedra, corners with three equivalent O(1)Eu5Ni octahedra, corners with three equivalent O(3)Sr2Eu3Ni octahedra, corners with three equivalent O(4)Sr2Eu3Ni octahedra, corners with three equivalent O(2)SrEu4Ni octahedra, edges with two equivalent O(5)SrEu3Ni2 octahedra,  a faceface with one O(1)Eu5Ni octahedra,  a faceface with one O(3)Sr2Eu3Ni octahedra,  a faceface with one O(4)Sr2Eu3Ni octahedra,  a faceface with one O(2)SrEu4Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 3-54°. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrEu3(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.765
_cell_length_b   6.765
_cell_length_c   5.380
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   132.915
_symmetry_Int_Tables_number   1
_cell_volume   180.305
_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
  Sr  Sr0  1  0.358  0.642  0.000  1.0
  Eu  Eu1  1  0.861  0.139  0.500  1.0
  Eu  Eu2  1  0.141  0.859  0.500  1.0
  Eu  Eu3  1  0.640  0.360  0.000  1.0
  Ni  Ni4  1  0.497  0.503  0.500  1.0
  Ni  Ni5  1  0.999  0.001  0.000  1.0
  O  O6  1  0.673  0.327  0.500  1.0
  O  O7  1  0.162  0.838  0.000  1.0
  O  O8  1  0.828  0.172  0.000  1.0
  O  O9  1  0.327  0.673  0.500  1.0
  O  O10  1  0.250  0.243  0.253  1.0
  O  O11  1  0.757  0.750  0.747  1.0
  O  O12  1  0.250  0.243  0.747  1.0
  O  O13  1  0.757  0.750  0.253  1.0
[/CIF]
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The crystal structure described by SrEu3(NiO4)2 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(5) atoms. There are three inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(5) atoms. In the second Eu site, Eu(2) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and four equivalent O(5) atoms. In the third Eu site, Eu(3) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and four equivalent O(5) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(4), and four equivalent O(5) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Ni site, Ni(2) is bonded to one O(2), one O(3), and four equivalent O(5) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Eu(1), two equivalent Eu(2), two equivalent Eu(3), and one Ni(1) atom to form distorted OEu5Ni octahedra that share  a cornercorner with one O(4)Sr2Eu3Ni octahedra, corners with four equivalent O(1)Eu5Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(3)Sr2Eu3Ni octahedra, edges with two equivalent O(4)Sr2Eu3Ni octahedra, edges with four equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-52°. In the second O site, O(2) is bonded to one Sr(1), two equivalent Eu(2), two equivalent Eu(3), and one Ni(2) atom to form distorted OSrEu4Ni octahedra that share  a cornercorner with one O(3)Sr2Eu3Ni octahedra, corners with four equivalent O(2)SrEu4Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(3)Sr2Eu3Ni octahedra, edges with two equivalent O(4)Sr2Eu3Ni octahedra, edges with four equivalent O(1)Eu5Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-54°. In the third O site, O(3) is bonded to two equivalent Sr(1), one Eu(3), two equivalent Eu(1), and one Ni(2) atom to form distorted OSr2Eu3Ni octahedra that share  a cornercorner with one O(2)SrEu4Ni octahedra, corners with four equivalent O(3)Sr2Eu3Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(1)Eu5Ni octahedra, edges with two equivalent O(2)SrEu4Ni octahedra, edges with four equivalent O(4)Sr2Eu3Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the fourth O site, O(4) is bonded to two equivalent Sr(1), one Eu(2), two equivalent Eu(1), and one Ni(1) atom to form distorted OSr2Eu3Ni octahedra that share  a cornercorner with one O(1)Eu5Ni octahedra, corners with four equivalent O(4)Sr2Eu3Ni octahedra, corners with twelve equivalent O(5)SrEu3Ni2 octahedra, edges with two equivalent O(1)Eu5Ni octahedra, edges with two equivalent O(2)SrEu4Ni octahedra, edges with four equivalent O(3)Sr2Eu3Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the fifth O site, O(5) is bonded to one Sr(1), one Eu(1), one Eu(2), one Eu(3), one Ni(1), and one Ni(2) atom to form distorted OSrEu3Ni2 octahedra that share corners with two equivalent O(5)SrEu3Ni2 octahedra, corners with three equivalent O(1)Eu5Ni octahedra, corners with three equivalent O(3)Sr2Eu3Ni octahedra, corners with three equivalent O(4)Sr2Eu3Ni octahedra, corners with three equivalent O(2)SrEu4Ni octahedra, edges with two equivalent O(5)SrEu3Ni2 octahedra,  a faceface with one O(1)Eu5Ni octahedra,  a faceface with one O(3)Sr2Eu3Ni octahedra,  a faceface with one O(4)Sr2Eu3Ni octahedra,  a faceface with one O(2)SrEu4Ni octahedra, and faces with four equivalent O(5)SrEu3Ni2 octahedra. The corner-sharing octahedral tilt angles range from 3-54°. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrEu3(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.765
_cell_length_b   6.765
_cell_length_c   5.380
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   132.915
_symmetry_Int_Tables_number   1
_cell_volume   180.305
_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
  Sr  Sr0  1  0.358  0.642  0.000  1.0
  Eu  Eu1  1  0.861  0.139  0.500  1.0
  Eu  Eu2  1  0.141  0.859  0.500  1.0
  Eu  Eu3  1  0.640  0.360  0.000  1.0
  Ni  Ni4  1  0.497  0.503  0.500  1.0
  Ni  Ni5  1  0.999  0.001  0.000  1.0
  O  O6  1  0.673  0.327  0.500  1.0
  O  O7  1  0.162  0.838  0.000  1.0
  O  O8  1  0.828  0.172  0.000  1.0
  O  O9  1  0.327  0.673  0.500  1.0
  O  O10  1  0.250  0.243  0.253  1.0
  O  O11  1  0.757  0.750  0.747  1.0
  O  O12  1  0.250  0.243  0.747  1.0
  O  O13  1  0.757  0.750  0.253  1.0
[/CIF]
.