The first examples of a new class of gallium hydride clusters with direct Ga-Ga bonds and common hydrocarbon structures are reported. Neutron powder diffraction was used to find a Ga[GaH3]45- cluster ion with a neopentane structure in a novel cubic structure type of Rb8Ga5H15. Another cluster ion with a polyethylene structure, [GaH2]nn-, was found in a second novel (RbGaH2)n hydride. These hydrocarbon-like clusters in gallium hydride materials have significant implications for the discovery of hydrides for hydrogen storage as well as for interesting electronic properties. © 2011 American Chemical Society.
