Al3Pt5 crystallizes in the orthorhombic Pbam space group. There are three inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a 6-coordinate geometry to two equivalent Al(2) and four equivalent Al(1) atoms. In the second Pt site, Pt(2) is bonded in a 5-coordinate geometry to one Al(2) and four equivalent Al(1) atoms. In the third Pt site, Pt(3) is bonded in a 6-coordinate geometry to two equivalent Al(2) and four equivalent Al(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to two equivalent Pt(3), four equivalent Pt(1), and four equivalent Pt(2) atoms. In the second Al site, Al(2) is bonded in a body-centered cubic geometry to two equivalent Pt(2), two equivalent Pt(3), and four equivalent Pt(1) atoms.
Al3Pt5 crystallizes in the orthorhombic Pbam space group. There are three inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a 6-coordinate geometry to two equivalent Al(2) and four equivalent Al(1) atoms. Both Pt(1)-Al(2) bond lengths are 2.56 Å. There are a spread of Pt(1)-Al(1) bond distances ranging from 2.60-2.87 Å. In the second Pt site, Pt(2) is bonded in a 5-coordinate geometry to one Al(2) and four equivalent Al(1) atoms. The Pt(2)-Al(2) bond length is 2.52 Å. There are two shorter (2.59 Å) and two longer (2.79 Å) Pt(2)-Al(1) bond lengths. In the third Pt site, Pt(3) is bonded in a 6-coordinate geometry to two equivalent Al(2) and four equivalent Al(1) atoms. Both Pt(3)-Al(2) bond lengths are 2.71 Å. All Pt(3)-Al(1) bond lengths are 2.68 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to two equivalent Pt(3), four equivalent Pt(1), and four equivalent Pt(2) atoms. In the second Al site, Al(2) is bonded in a body-centered cubic geometry to two equivalent Pt(2), two equivalent Pt(3), and four equivalent Pt(1) atoms.