Reactions of [Pt(AuPPh(3))(8)](NO3)(2) with M(I) species (M = Cu, Au) under H-2-atmosphere yield several new hydride-containing mixed-metal-gold phosphine cluster compounds. Two new hydride-containing PtAuCu clusters are obtained in this way; [Pt(H)(CuCl)(AuPPh(3))(8)](NO3) (1) and [Pt(H)(CuCl)(2)(AuPPh(3))(8)](NO3) (2). Considerations on the solvent dependency show that the Bronsted acidity of the solvent used is crucial in controlling the formation of 1 or 2. Clusters 1 and 2 were characterized by elemental analyses, ICP analyses, and IR and NMR (P-31 and Pt-195) Spectroscopy; their crystal and molecular structures have been determined by single-crystal X-ray analyses. Compound crystallizes in the monoclinic space group P2(1), with Z = 2, a = 15.284(8) Angstrom, b = 26.004(2) Angstrom, c = 16.558(2) Angstrom, beta = 95.27(5)degrees, and V = 6636 Angstrom(3); MO K alpha radiation was used. The residuals are R = 0.083 and wR(2) = 0.18 for 10 495 observed reflections and 372 variables. 2 crystallizes in the triclinic space group P (1) over bar, with Z = 2, a 15.349(4) Angstrom, b = 16.949(2) Angstrom, c = 29.037(7) Angstrom, alpha = 78.95(1)0, beta = 74.87(2)degrees, gamma = 84.74(2)degrees, and gamma = 7150 Angstrom 3; MO K alpha radiation was used. The residuals are R = 0.085 and wR(2) = 0.22 for 15308 observed reflections and 773 variables. Both clusters have a central platinum atom surrounded by eight gold atoms and one (for 1) or two (for 2) copper atoms; the gold atoms are attached to triphenylphosphine ligands, whereas the copper atoms are attached to chloride ligands. The crystal structures of 1 and 2 show that the copper atoms in these clusters are located "trans" to the hydride ligand. [Pt(H)(PPh(3))(CuCl)(AuPPh(3))(6)](+) (5) is obtained from the reaction of the cluster [Pt(H)(PPh(3))(AuPPh(3))(7)](NO3)2 with [PPh(3)CuCl](4). 5 was characterized by IR, H-1 NMR, 319 NMR and Pt-195 NMR spectroscopy and by FAB-MS. In addition to these PtAuCu clusters this paper also reports several new PtHAu9 cluster compounds : [Pt(H)(AuPy)(AuPPh(3))(8)](NO3)(2) (3) (in which Py = C5H4N), [Pt(H)(AuCl)(AuPPh(3))(8)](NO3) (4a), [Pt(H)(AuBr)(AuPPh(3))(8)](Br) (4b), and [Pt(H)(AuSCN)(AuPPh(3))(8)](SCN) (4c). The pyridine ligand of 3 can be substituted easily by Cl-, Br- or SCN- to give 4a, 4b, or 4c, respectively. The thiocyanate ligand of 4c is shown to be sulfur-coordinated to a gold atom.