Homonuclear multiple bonding in heavier main group elements

Bonding in the Si2H2 isomers: A topographical study

“…We suggest this resonance mixture (of unknown composition, just as in the amide case) contributes to the isosurface structure seen and may be taken as the signature of the slipped triple bond in trans bent Si 2 H 2 . The lone pair character of multiple bonds for the heavier elements has been discussed by Power [3,4].…”

Turning a Transition State into a Minimum—The Nature of the Bonding in Diplumbylene Compounds RPbPbR (R=H, Ar)

“…The former species have a skeleton with a nonplanar geometry and the EE bonding is rather weak, which is evident from the fact that many compounds dissociate in solution. [3] Much less is known about the heavier Group 14 analogues of alkynes REER. Theoretical studies predicted that the energetically lowest lying structures of Si 2 H 2 and Ge 2 H 2 are very different from the linear equilibrium geometry of acetylene (Figure 1).…”

Synthesis of the Square-Planar Gallium Species K2[Ga4(C6H3-2,6-Trip2)2] (Trip=C6H2-2,4,6-iPr3): The Role of Aryl–Alkali Metal Ion Interactions in the Structure of Gallium Clusters

“…[7] Density functional theory (DFT) calculations [8] on the model compounds for 7 ± 9, Na 2 [(GaC 6 H 3 -2,6-Ph 2 ) 2 ] (8), and Na 2 [(GaPh) 2 ] (9), suggest that such effects are structurally important since the GaÀGa distance in 8 (2.362 ), which has Na ± aryl interactions, is about 0.1 shorter than that in 9 (2.461 ) which has no Na ± aryl contacts. [5] In an earlier publication [9] it was suggested that the structural effects of the Na ions in 7 could be investigated by synthesizing a solvent-separated species of the type [NaL n ] 2 [(GaC 6 H 3 -2,6-Trip 2 ) 2 ] (L complexing ligand; e. g., crown ether or cryptand) with no Na ± aryl interactions. Unfortunately, no species of this type are known.…”