Digallane

Digallane is a chemical compound with the formula Ga2H6. It is a dimer of the unstable monomer gallane, GaH3. In terms of structure, digallane is analogous to diborane, B2H6. It consists of two gallium atoms bridged by two hydrogen atoms, with each gallium atom also bonded to two terminal hydrogen atoms. The bridging hydrogen atoms are located in the space between the two gallium atoms.

Digallane is a colorless gas at room temperature. It is known to be highly reactive and pyrophoric, meaning it ignites spontaneously in air. This reactivity stems from the electron-deficient nature of the gallium atoms and the strained nature of the bridging hydrogen bonds. Due to its instability and reactivity, digallane is not commonly encountered or used in most chemical applications. Its synthesis and handling require specialized techniques and inert atmosphere conditions.

The compound can be prepared by the reduction of gallium halides with metal hydrides, such as lithium aluminum hydride, under specific conditions. Research into digallane and other higher metal hydrides is primarily of academic interest, contributing to the understanding of chemical bonding and the properties of Group 13 elements. The analogous compounds with heavier elements in Group 13, such as dialuminum and diindium hydrides, exhibit similar structural and chemical characteristics.