EuNi9Ge4 crystallizes in the tetragonal I4/mcm space group. Eu(1) is bonded in a 24-coordinate geometry to eight equivalent Ni(1), eight equivalent Ni(3), and eight equivalent Ge(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to two equivalent Eu(1), one Ni(1), one Ni(2), four equivalent Ni(3), and four equivalent Ge(1) atoms. In the second Ni site, Ni(2) is bonded in a cuboctahedral geometry to four equivalent Ni(1), four equivalent Ni(3), and four equivalent Ge(1) atoms. In the third Ni site, Ni(3) is bonded in a 12-coordinate geometry to two equivalent Eu(1), one Ni(2), three equivalent Ni(3), four equivalent Ni(1), and two equivalent Ge(1) atoms. Ge(1) is bonded in a 12-coordinate geometry to two equivalent Eu(1), one Ni(2), two equivalent Ni(3), four equivalent Ni(1), and three equivalent Ge(1) atoms.
EuNi9Ge4 crystallizes in the tetragonal I4/mcm space group. Eu(1) is bonded in a 24-coordinate geometry to eight equivalent Ni(1), eight equivalent Ni(3), and eight equivalent Ge(1) atoms. All Eu(1)-Ni(1) bond lengths are 3.43 Å. All Eu(1)-Ni(3) bond lengths are 3.48 Å. All Eu(1)-Ge(1) bond lengths are 3.40 Å. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to two equivalent Eu(1), one Ni(1), one Ni(2), four equivalent Ni(3), and four equivalent Ge(1) atoms. The Ni(1)-Ni(1) bond length is 2.65 Å. The Ni(1)-Ni(2) bond length is 2.55 Å. There are a spread of Ni(1)-Ni(3) bond distances ranging from 2.43-2.66 Å. There are two shorter (2.55 Å) and two longer (2.59 Å) Ni(1)-Ge(1) bond lengths. In the second Ni site, Ni(2) is bonded in a cuboctahedral geometry to four equivalent Ni(1), four equivalent Ni(3), and four equivalent Ge(1) atoms. All Ni(2)-Ni(3) bond lengths are 2.45 Å. All Ni(2)-Ge(1) bond lengths are 2.43 Å. In the third Ni site, Ni(3) is bonded in a 12-coordinate geometry to two equivalent Eu(1), one Ni(2), three equivalent Ni(3), four equivalent Ni(1), and two equivalent Ge(1) atoms. There are two shorter (2.49 Å) and one longer (2.72 Å) Ni(3)-Ni(3) bond length. Both Ni(3)-Ge(1) bond lengths are 2.52 Å. Ge(1) is bonded in a 12-coordinate geometry to two equivalent Eu(1), one Ni(2), two equivalent Ni(3), four equivalent Ni(1), and three equivalent Ge(1) atoms. There are two shorter (2.68 Å) and one longer (2.70 Å) Ge(1)-Ge(1) bond length.