Y6Pt5Ga17 crystallizes in the monoclinic C2/m space group. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to one Ga(1), one Ga(2), one Ga(3), one Ga(4), two equivalent Ga(5), two equivalent Ga(6), two equivalent Ga(7), and two equivalent Ga(8) atoms to form distorted YGa12 cuboctahedra that share  an edgeedge with one Ga(9)Y4Ga4Pt4 cuboctahedra and faces with two equivalent Y(1)Ga12 cuboctahedra. In the second Y site, Y(2) is bonded in a 14-coordinate geometry to two equivalent Pt(2), one Ga(3), two equivalent Ga(4), two equivalent Ga(6), two equivalent Ga(8), two equivalent Ga(9), and three equivalent Ga(1) atoms. In the third Y site, Y(3) is bonded in a 12-coordinate geometry to two equivalent Pt(1), two equivalent Pt(3), one Ga(4), two equivalent Ga(2), two equivalent Ga(3), two equivalent Ga(5), and two equivalent Ga(7) atoms. There are three inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a 8-coordinate geometry to two equivalent Y(3), one Ga(5), one Ga(8), two equivalent Ga(2), and two equivalent Ga(3) atoms. In the second Pt site, Pt(2) is bonded in a 10-coordinate geometry to two equivalent Y(2), one Ga(6), one Ga(7), two equivalent Ga(1), two equivalent Ga(4), and two equivalent Ga(9) atoms. In the third Pt site, Pt(3) is bonded in a 4-coordinate geometry to four equivalent Y(3), two equivalent Ga(2), and two equivalent Ga(3) atoms. There are nine inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 10-coordinate geometry to one Y(1), three equivalent Y(2), two equivalent Pt(2), one Ga(9), and three equivalent Ga(6) atoms. In the second Ga site, Ga(2) is bonded in a 3-coordinate geometry to one Y(1), two equivalent Y(3), one Pt(3), two equivalent Pt(1), and three equivalent Ga(5) atoms. In the third Ga site, Ga(3) is bonded in a 10-coordinate geometry to one Y(1), one Y(2), two equivalent Y(3), one Pt(3), two equivalent Pt(1), one Ga(7), and two equivalent Ga(8) atoms. In the fourth Ga site, Ga(4) is bonded in a 10-coordinate geometry to one Y(1), one Y(3), two equivalent Y(2), two equivalent Pt(2), one Ga(8), one Ga(9), and two equivalent Ga(7) atoms. In the fifth Ga site, Ga(5) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(3), one Pt(1), one Ga(7), and three equivalent Ga(2) atoms. In the sixth Ga site, Ga(6) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(2), one Pt(2), one Ga(8), and three equivalent Ga(1) atoms. In the seventh Ga site, Ga(7) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(3), one Pt(2), one Ga(3), one Ga(5), and two equivalent Ga(4) atoms. In the eighth Ga site, Ga(8) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(2), one Pt(1), one Ga(4), one Ga(6), and two equivalent Ga(3) atoms. In the ninth Ga site, Ga(9) is bonded to four equivalent Y(2), four equivalent Pt(2), two equivalent Ga(1), and two equivalent Ga(4) atoms to form distorted GaY4Ga4Pt4 cuboctahedra that share edges with two equivalent Y(1)Ga12 cuboctahedra and faces with two equivalent Ga(9)Y4Ga4Pt4 cuboctahedra.
Y6Pt5Ga17 crystallizes in the monoclinic C2/m space group. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to one Ga(1), one Ga(2), one Ga(3), one Ga(4), two equivalent Ga(5), two equivalent Ga(6), two equivalent Ga(7), and two equivalent Ga(8) atoms to form distorted YGa12 cuboctahedra that share  an edgeedge with one Ga(9)Y4Ga4Pt4 cuboctahedra and faces with two equivalent Y(1)Ga12 cuboctahedra. The Y(1)-Ga(1) bond length is 3.26 Å. The Y(1)-Ga(2) bond length is 3.19 Å. The Y(1)-Ga(3) bond length is 3.19 Å. The Y(1)-Ga(4) bond length is 3.23 Å. Both Y(1)-Ga(5) bond lengths are 3.19 Å. Both Y(1)-Ga(6) bond lengths are 3.16 Å. Both Y(1)-Ga(7) bond lengths are 3.20 Å. Both Y(1)-Ga(8) bond lengths are 3.17 Å. In the second Y site, Y(2) is bonded in a 14-coordinate geometry to two equivalent Pt(2), one Ga(3), two equivalent Ga(4), two equivalent Ga(6), two equivalent Ga(8), two equivalent Ga(9), and three equivalent Ga(1) atoms. There is one shorter (3.06 Å) and one longer (3.07 Å) Y(2)-Pt(2) bond length. The Y(2)-Ga(3) bond length is 3.45 Å. Both Y(2)-Ga(4) bond lengths are 3.14 Å. Both Y(2)-Ga(6) bond lengths are 3.08 Å. Both Y(2)-Ga(8) bond lengths are 3.04 Å. Both Y(2)-Ga(9) bond lengths are 3.29 Å. There are two shorter (3.11 Å) and one longer (3.34 Å) Y(2)-Ga(1) bond length. In the third Y site, Y(3) is bonded in a 12-coordinate geometry to two equivalent Pt(1), two equivalent Pt(3), one Ga(4), two equivalent Ga(2), two equivalent Ga(3), two equivalent Ga(5), and two equivalent Ga(7) atoms. There is one shorter (3.08 Å) and one longer (3.09 Å) Y(3)-Pt(1) bond length. Both Y(3)-Pt(3) bond lengths are 3.19 Å. The Y(3)-Ga(4) bond length is 3.42 Å. Both Y(3)-Ga(2) bond lengths are 3.11 Å. Both Y(3)-Ga(3) bond lengths are 3.09 Å. Both Y(3)-Ga(5) bond lengths are 3.09 Å. Both Y(3)-Ga(7) bond lengths are 3.11 Å. There are three inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a 8-coordinate geometry to two equivalent Y(3), one Ga(5), one Ga(8), two equivalent Ga(2), and two equivalent Ga(3) atoms. The Pt(1)-Ga(5) bond length is 2.54 Å. The Pt(1)-Ga(8) bond length is 2.54 Å. Both Pt(1)-Ga(2) bond lengths are 2.70 Å. Both Pt(1)-Ga(3) bond lengths are 2.71 Å. In the second Pt site, Pt(2) is bonded in a 10-coordinate geometry to two equivalent Y(2), one Ga(6), one Ga(7), two equivalent Ga(1), two equivalent Ga(4), and two equivalent Ga(9) atoms. The Pt(2)-Ga(6) bond length is 2.58 Å. The Pt(2)-Ga(7) bond length is 2.60 Å. Both Pt(2)-Ga(1) bond lengths are 2.80 Å. Both Pt(2)-Ga(4) bond lengths are 2.76 Å. Both Pt(2)-Ga(9) bond lengths are 2.83 Å. In the third Pt site, Pt(3) is bonded in a 4-coordinate geometry to four equivalent Y(3), two equivalent Ga(2), and two equivalent Ga(3) atoms. Both Pt(3)-Ga(2) bond lengths are 2.63 Å. Both Pt(3)-Ga(3) bond lengths are 2.64 Å. There are nine inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 10-coordinate geometry to one Y(1), three equivalent Y(2), two equivalent Pt(2), one Ga(9), and three equivalent Ga(6) atoms. The Ga(1)-Ga(9) bond length is 2.73 Å. There are two shorter (2.62 Å) and one longer (2.67 Å) Ga(1)-Ga(6) bond length. In the second Ga site, Ga(2) is bonded in a 3-coordinate geometry to one Y(1), two equivalent Y(3), one Pt(3), two equivalent Pt(1), and three equivalent Ga(5) atoms. There is one shorter (2.64 Å) and two longer (2.68 Å) Ga(2)-Ga(5) bond lengths. In the third Ga site, Ga(3) is bonded in a 10-coordinate geometry to one Y(1), one Y(2), two equivalent Y(3), one Pt(3), two equivalent Pt(1), one Ga(7), and two equivalent Ga(8) atoms. The Ga(3)-Ga(7) bond length is 2.68 Å. Both Ga(3)-Ga(8) bond lengths are 2.67 Å. In the fourth Ga site, Ga(4) is bonded in a 10-coordinate geometry to one Y(1), one Y(3), two equivalent Y(2), two equivalent Pt(2), one Ga(8), one Ga(9), and two equivalent Ga(7) atoms. The Ga(4)-Ga(8) bond length is 2.64 Å. The Ga(4)-Ga(9) bond length is 2.71 Å. Both Ga(4)-Ga(7) bond lengths are 2.61 Å. In the fifth Ga site, Ga(5) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(3), one Pt(1), one Ga(7), and three equivalent Ga(2) atoms. The Ga(5)-Ga(7) bond length is 2.56 Å. In the sixth Ga site, Ga(6) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(2), one Pt(2), one Ga(8), and three equivalent Ga(1) atoms. The Ga(6)-Ga(8) bond length is 2.51 Å. In the seventh Ga site, Ga(7) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(3), one Pt(2), one Ga(3), one Ga(5), and two equivalent Ga(4) atoms. In the eighth Ga site, Ga(8) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(2), one Pt(1), one Ga(4), one Ga(6), and two equivalent Ga(3) atoms. In the ninth Ga site, Ga(9) is bonded to four equivalent Y(2), four equivalent Pt(2), two equivalent Ga(1), and two equivalent Ga(4) atoms to form distorted GaY4Ga4Pt4 cuboctahedra that share edges with two equivalent Y(1)Ga12 cuboctahedra and faces with two equivalent Ga(9)Y4Ga4Pt4 cuboctahedra.