Eu3Tc is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to four equivalent Eu(2) and four equivalent Tc(1) atoms to form distorted EuEu4Tc4 cuboctahedra that share corners with eight equivalent Eu(1)Eu4Tc4 cuboctahedra, corners with eight equivalent Eu(2)Eu8Tc4 cuboctahedra, corners with eight equivalent Tc(1)Eu12 cuboctahedra, edges with four equivalent Eu(2)Eu8Tc4 cuboctahedra, edges with four equivalent Tc(1)Eu12 cuboctahedra, edges with twelve equivalent Eu(1)Eu4Tc4 cuboctahedra, and faces with six equivalent Eu(1)Eu4Tc4 cuboctahedra. In the second Eu site, Eu(2) is bonded to eight equivalent Eu(1) and four equivalent Tc(1) atoms to form EuEu8Tc4 cuboctahedra that share corners with four equivalent Eu(2)Eu8Tc4 cuboctahedra, corners with eight equivalent Tc(1)Eu12 cuboctahedra, corners with sixteen equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Eu(2)Eu8Tc4 cuboctahedra, faces with four equivalent Eu(2)Eu8Tc4 cuboctahedra, and faces with six equivalent Tc(1)Eu12 cuboctahedra. Tc(1) is bonded to four equivalent Eu(2) and eight equivalent Eu(1) atoms to form TcEu12 cuboctahedra that share corners with four equivalent Tc(1)Eu12 cuboctahedra, corners with eight equivalent Eu(2)Eu8Tc4 cuboctahedra, corners with sixteen equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Tc(1)Eu12 cuboctahedra, faces with four equivalent Tc(1)Eu12 cuboctahedra, and faces with six equivalent Eu(2)Eu8Tc4 cuboctahedra.
Eu3Tc is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to four equivalent Eu(2) and four equivalent Tc(1) atoms to form distorted EuEu4Tc4 cuboctahedra that share corners with eight equivalent Eu(1)Eu4Tc4 cuboctahedra, corners with eight equivalent Eu(2)Eu8Tc4 cuboctahedra, corners with eight equivalent Tc(1)Eu12 cuboctahedra, edges with four equivalent Eu(2)Eu8Tc4 cuboctahedra, edges with four equivalent Tc(1)Eu12 cuboctahedra, edges with twelve equivalent Eu(1)Eu4Tc4 cuboctahedra, and faces with six equivalent Eu(1)Eu4Tc4 cuboctahedra. All Eu(1)-Eu(2) bond lengths are 3.41 Å. All Eu(1)-Tc(1) bond lengths are 3.41 Å. In the second Eu site, Eu(2) is bonded to eight equivalent Eu(1) and four equivalent Tc(1) atoms to form EuEu8Tc4 cuboctahedra that share corners with four equivalent Eu(2)Eu8Tc4 cuboctahedra, corners with eight equivalent Tc(1)Eu12 cuboctahedra, corners with sixteen equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Eu(2)Eu8Tc4 cuboctahedra, faces with four equivalent Eu(2)Eu8Tc4 cuboctahedra, and faces with six equivalent Tc(1)Eu12 cuboctahedra. All Eu(2)-Tc(1) bond lengths are 3.49 Å. Tc(1) is bonded to four equivalent Eu(2) and eight equivalent Eu(1) atoms to form TcEu12 cuboctahedra that share corners with four equivalent Tc(1)Eu12 cuboctahedra, corners with eight equivalent Eu(2)Eu8Tc4 cuboctahedra, corners with sixteen equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Eu(1)Eu4Tc4 cuboctahedra, edges with eight equivalent Tc(1)Eu12 cuboctahedra, faces with four equivalent Tc(1)Eu12 cuboctahedra, and faces with six equivalent Eu(2)Eu8Tc4 cuboctahedra.