Be5(FeAl2)2 crystallizes in the monoclinic C2/m space group. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to two equivalent Be(1), two equivalent Be(3), two equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms to form a mixture of distorted edge, corner, and face-sharing BeBe4Al6Fe2 cuboctahedra. In the second Be site, Be(2) is bonded in a 2-coordinate geometry to two equivalent Fe(1) and four equivalent Al(2) atoms. In the third Be site, Be(3) is bonded to four equivalent Be(1), two equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms to form a mixture of distorted edge, corner, and face-sharing BeBe4Al6Fe2 cuboctahedra. Fe(1) is bonded in a distorted q6 geometry to one Be(3), two equivalent Be(1), two equivalent Be(2), three equivalent Al(1), and three equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 3-coordinate geometry to two equivalent Be(3), four equivalent Be(1), three equivalent Fe(1), and three equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 14-coordinate geometry to one Be(3), two equivalent Be(1), four equivalent Be(2), three equivalent Fe(1), one Al(2), and three equivalent Al(1) atoms.
Be5(FeAl2)2 crystallizes in the monoclinic C2/m space group. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to two equivalent Be(1), two equivalent Be(3), two equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms to form a mixture of distorted edge, corner, and face-sharing BeBe4Al6Fe2 cuboctahedra. Both Be(1)-Be(1) bond lengths are 2.19 Å. Both Be(1)-Be(3) bond lengths are 2.18 Å. Both Be(1)-Fe(1) bond lengths are 2.26 Å. Both Be(1)-Al(2) bond lengths are 2.64 Å. There are two shorter (2.64 Å) and two longer (2.65 Å) Be(1)-Al(1) bond lengths. In the second Be site, Be(2) is bonded in a 2-coordinate geometry to two equivalent Fe(1) and four equivalent Al(2) atoms. Both Be(2)-Fe(1) bond lengths are 2.23 Å. There are two shorter (2.47 Å) and two longer (2.81 Å) Be(2)-Al(2) bond lengths. In the third Be site, Be(3) is bonded to four equivalent Be(1), two equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms to form a mixture of distorted edge, corner, and face-sharing BeBe4Al6Fe2 cuboctahedra. Both Be(3)-Fe(1) bond lengths are 2.24 Å. Both Be(3)-Al(2) bond lengths are 2.61 Å. All Be(3)-Al(1) bond lengths are 2.65 Å. Fe(1) is bonded in a distorted q6 geometry to one Be(3), two equivalent Be(1), two equivalent Be(2), three equivalent Al(1), and three equivalent Al(2) atoms. There are two shorter (2.54 Å) and one longer (2.56 Å) Fe(1)-Al(1) bond length. There is one shorter (2.50 Å) and two longer (2.59 Å) Fe(1)-Al(2) bond lengths. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 3-coordinate geometry to two equivalent Be(3), four equivalent Be(1), three equivalent Fe(1), and three equivalent Al(2) atoms. There are two shorter (2.64 Å) and one longer (2.67 Å) Al(1)-Al(2) bond length. In the second Al site, Al(2) is bonded in a 14-coordinate geometry to one Be(3), two equivalent Be(1), four equivalent Be(2), three equivalent Fe(1), one Al(2), and three equivalent Al(1) atoms. The Al(2)-Al(2) bond length is 2.99 Å.