The unusual Y-shaped structure of the recently reported three-coordinate Pt complex Pt[NHC(Dip)(2)]-(SiMe2Ph)(2) (NHC = N-heterocyclic carbene; Dip = 2,6-diisopropylphenyl) was considered a snapshot of the reductive elimination of disilane. A density functional theory study indicates that this structure arises from the strong trans influence of the extremely sigma-donating carbene and silyl ligands. Though this complex can be understood to be a Pt(II) disilyl complex bearing a distorted geometry due to the Jahn-Teller effect, its Pt-195 NMR chemical shift is considerably different from those of Pt(II) complexes but close to those of typical Pt(0) complexes. Its Si center dot center dot center dot Si bonding interaction is similar to 50% of the usual energy of a Si-Si single bond. The interaction between the Pt center and the (SiMe2Ph)(2) moiety can be understood in terms of donation and back-donation interactions of the Si-Si sigma-bonding and sigma*-antibonding molecular orbitals with the Pt center. Thus, we conclude that this is likely a Pt(0) sigma-disilane complex and thus a snapshot after a considerable amount of the charge transfer from disilane to the Pt center has occurred. Phenyl anion (Ph-) and [R-Ar](-) [R-Ar = 2,6-(2,6-iPr(2)C(6)H(3))(2)C6H3] as well as the divalent carbon(0) ligand C(NHC)(2) also provide similar unusual Y-shaped structures. Three-coordinate digermyl, diboryl, and silyl-boryl complexes of Pt and a disilyl complex of Pd are theoretically predicted to have similar unusual Y-shaped structures when a strongly donating ligand coordinates to the metal center. In a trigonal-bipyramidal Ir disilyl complex [Ir{NHC(Dip)(2)}-(PH3)(2)(SiMe3)(2)](+), the equatorial plane has a similar unusual Y-shaped structure. These results suggest that various snapshots can be shown for the reductive eliminations of the Ge-Ge, B-B, and B-Si sigma-bonds.