Pt9Cu3B5 crystallizes in the hexagonal P-62m space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a 7-coordinate geometry to four equivalent Cu(1), one B(1), and two equivalent B(2) atoms. In the second Pt site, Pt(2) is bonded in a 5-coordinate geometry to one Cu(1) and four equivalent B(1) atoms. Cu(1) is bonded in a 11-coordinate geometry to one Pt(2), eight equivalent Pt(1), and two equivalent B(2) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded to two equivalent Pt(1) and four equivalent Pt(2) atoms to form a mixture of distorted edge and corner-sharing BPt6 pentagonal pyramids. In the second B site, B(2) is bonded in a 6-coordinate geometry to six equivalent Pt(1) and three equivalent Cu(1) atoms.
Pt9Cu3B5 crystallizes in the hexagonal P-62m space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a 7-coordinate geometry to four equivalent Cu(1), one B(1), and two equivalent B(2) atoms. There are two shorter (2.68 Å) and two longer (2.81 Å) Pt(1)-Cu(1) bond lengths. The Pt(1)-B(1) bond length is 2.21 Å. Both Pt(1)-B(2) bond lengths are 2.21 Å. In the second Pt site, Pt(2) is bonded in a 5-coordinate geometry to one Cu(1) and four equivalent B(1) atoms. The Pt(2)-Cu(1) bond length is 2.54 Å. All Pt(2)-B(1) bond lengths are 2.22 Å. Cu(1) is bonded in a 11-coordinate geometry to one Pt(2), eight equivalent Pt(1), and two equivalent B(2) atoms. Both Cu(1)-B(2) bond lengths are 2.64 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded to two equivalent Pt(1) and four equivalent Pt(2) atoms to form a mixture of distorted edge and corner-sharing BPt6 pentagonal pyramids. In the second B site, B(2) is bonded in a 6-coordinate geometry to six equivalent Pt(1) and three equivalent Cu(1) atoms.