Materials Data on NaEu3 by Materials Project
NaEu3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Na is bonded to twelve Eu atoms to form NaEu12 cuboctahedra that share corners with four equivalent NaEu12 cuboctahedra, corners with eight equivalent EuNa4Eu8 cuboctahedra, edges with eight equivalent NaEu12 cuboctahedra, edges with sixteen equivalent EuNa4Eu8 cuboctahedra, faces with four equivalent NaEu12 cuboctahedra, and faces with fourteen EuNa4Eu8 cuboctahedra. There are four shorter (3.87 Å) and eight longer (4.04 Å) Na–Eu bond lengths. There are two inequivalent Eu sites. In the first Eu site, Eu is bonded to four equivalent Na and eight Eu atoms to form EuNa4Eu8 cuboctahedra that share corners with twelve equivalent EuNa4Eu8 cuboctahedra, edges with eight equivalent NaEu12 cuboctahedra, edges with sixteen EuNa4Eu8 cuboctahedra, faces with four equivalent NaEu12 cuboctahedra, and faces with fourteen EuNa4Eu8 cuboctahedra. There are four shorter (3.87 Å) and four longer (4.04 Å) Eu–Eu bond lengths. In the second Eu site, Eu is bonded to four equivalent Na and eight equivalent Eu atoms to form distorted EuNa4Eu8 cuboctahedra that share corners with four equivalent EuNa4Eu8 cuboctahedra, corners with eight equivalent NaEu12 cuboctahedra, edges with twenty-four EuNa4Eu8 cuboctahedra, faces with six equivalent NaEu12 cuboctahedra, and faces with twelve EuNa4Eu8 cuboctahedra.