NaEuCr4O12 crystallizes in the orthorhombic Amm2 space group. Na(1) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(5) atoms. Eu(1) is bonded in a 10-coordinate geometry to two equivalent O(2), four equivalent O(1), and four equivalent O(4) atoms. Cr(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form corner-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles range from 19-34°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Eu(1) and two equivalent Cr(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Eu(1) and two equivalent Cr(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1) and two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Eu(1) and two equivalent Cr(1) atoms. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Na(1) and two equivalent Cr(1) atoms.
NaEuCr4O12 crystallizes in the orthorhombic Amm2 space group. Na(1) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(5) atoms. Both Na(1)-O(3) bond lengths are 2.29 Å. Both Na(1)-O(5) bond lengths are 2.37 Å. Eu(1) is bonded in a 10-coordinate geometry to two equivalent O(2), four equivalent O(1), and four equivalent O(4) atoms. Both Eu(1)-O(2) bond lengths are 2.51 Å. All Eu(1)-O(1) bond lengths are 2.38 Å. There are two shorter (2.62 Å) and two longer (2.75 Å) Eu(1)-O(4) bond lengths. Cr(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form corner-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles range from 19-34°. The Cr(1)-O(2) bond length is 1.90 Å. The Cr(1)-O(3) bond length is 1.87 Å. The Cr(1)-O(4) bond length is 1.96 Å. The Cr(1)-O(5) bond length is 1.84 Å. There is one shorter (1.78 Å) and one longer (2.15 Å) Cr(1)-O(1) bond length. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Eu(1) and two equivalent Cr(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Eu(1) and two equivalent Cr(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1) and two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Eu(1) and two equivalent Cr(1) atoms. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Na(1) and two equivalent Cr(1) atoms.