The cationic acyl(hydroxycarbene)platinum(II) complexes [Pt-2(bpy)(2){mu-(COMe)(2)H}(2)] [PF6](2) (4) (bpy = 2,2'-bipyridine) and [Pt-2(CoMe)(2)(bpy)(2){mu-(COMe)(2)H}]PF6 (5) have been prepared by reaction of the acyl(hydrido)platinum(IV) complex [PtCl(H)(COMe)(2)(bpy)] (2a) with TIPF6. The complexes 4 and 5 have been shown to be stable in the solid state up to 160 degrees C. The identities of 4 and 5 were determined by microanalysis, NMR (H-1, C-13), and IR spectroscopies. The crystal structures of 4, 5 (with two independent molecules in the asymmetric unit), and of 5 . Me2CO show that these are dinuclear complexes with square-planar platinum centers. In complex 4 these centers are bridged by two mu-acyl(hydroxycarbene) Ligands. In complex 5 the dinuclear structure is supported by one bridging acyl(hydroxycarbene) ligand and an additional d(8)-d(8) interaction between the two Pt centers [3.340(1)-3.542(1) Angstrom]. The O ... O distances were found to be 2.455(5) Angstrom (4) and 2.42(1)-2.44(1) Angstrom (5), corresponding to strong hydrogen bonds.