SrEuNiO4 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4mm space group. Sr(1) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(1), and four equivalent O(3) atoms. Eu(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(2) atoms. Ni(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Eu(1), and two equivalent Ni(1) atoms to form distorted OSr2Eu2Ni2 octahedra that share corners with two equivalent O(1)Sr2Eu2Ni2 octahedra, corners with six equivalent O(3)Sr4EuNi octahedra, corners with six equivalent O(2)SrEu4Ni octahedra, edges with two equivalent O(1)Sr2Eu2Ni2 octahedra, faces with two equivalent O(3)Sr4EuNi octahedra, faces with two equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(1)Sr2Eu2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 6-54°. In the second O site, O(2) is bonded to one Sr(1), four equivalent Eu(1), and one Ni(1) atom to form distorted OSrEu4Ni octahedra that share  a cornercorner with one O(3)Sr4EuNi octahedra, corners with four equivalent O(2)SrEu4Ni octahedra, corners with twelve equivalent O(1)Sr2Eu2Ni2 octahedra, edges with four equivalent O(3)Sr4EuNi octahedra, edges with four equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(1)Sr2Eu2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the third O site, O(3) is bonded to four equivalent Sr(1), one Eu(1), and one Ni(1) atom to form distorted OSr4EuNi octahedra that share  a cornercorner with one O(2)SrEu4Ni octahedra, corners with four equivalent O(3)Sr4EuNi octahedra, corners with twelve equivalent O(1)Sr2Eu2Ni2 octahedra, edges with four equivalent O(3)Sr4EuNi octahedra, edges with four equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(1)Sr2Eu2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-54°.
SrEuNiO4 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4mm space group. Sr(1) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(1), and four equivalent O(3) atoms. The Sr(1)-O(2) bond length is 2.42 Å. All Sr(1)-O(1) bond lengths are 2.65 Å. All Sr(1)-O(3) bond lengths are 2.73 Å. Eu(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(2) atoms. The Eu(1)-O(3) bond length is 2.34 Å. All Eu(1)-O(1) bond lengths are 2.51 Å. All Eu(1)-O(2) bond lengths are 2.72 Å. Ni(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 6°. The Ni(1)-O(2) bond length is 1.99 Å. The Ni(1)-O(3) bond length is 2.07 Å. All Ni(1)-O(1) bond lengths are 1.92 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Eu(1), and two equivalent Ni(1) atoms to form distorted OSr2Eu2Ni2 octahedra that share corners with two equivalent O(1)Sr2Eu2Ni2 octahedra, corners with six equivalent O(3)Sr4EuNi octahedra, corners with six equivalent O(2)SrEu4Ni octahedra, edges with two equivalent O(1)Sr2Eu2Ni2 octahedra, faces with two equivalent O(3)Sr4EuNi octahedra, faces with two equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(1)Sr2Eu2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 6-54°. In the second O site, O(2) is bonded to one Sr(1), four equivalent Eu(1), and one Ni(1) atom to form distorted OSrEu4Ni octahedra that share  a cornercorner with one O(3)Sr4EuNi octahedra, corners with four equivalent O(2)SrEu4Ni octahedra, corners with twelve equivalent O(1)Sr2Eu2Ni2 octahedra, edges with four equivalent O(3)Sr4EuNi octahedra, edges with four equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(1)Sr2Eu2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the third O site, O(3) is bonded to four equivalent Sr(1), one Eu(1), and one Ni(1) atom to form distorted OSr4EuNi octahedra that share  a cornercorner with one O(2)SrEu4Ni octahedra, corners with four equivalent O(3)Sr4EuNi octahedra, corners with twelve equivalent O(1)Sr2Eu2Ni2 octahedra, edges with four equivalent O(3)Sr4EuNi octahedra, edges with four equivalent O(2)SrEu4Ni octahedra, and faces with four equivalent O(1)Sr2Eu2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-54°.