title: Two new cluster ions, Ga[GaH3]4(5-) with a neopentane structure in Rb8Ga5H15 and [GaH2]n(n-) with a polyethylene structure in Rb(n)(GaH2)n, represent a new class of compounds with direct Ga-Ga bonds mimicking common hydrocarbons.
abstract: 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[GaH(3)](4)(5-) cluster ion with a neopentane structure in a novel cubic structure type of Rb(8)Ga(5)H(15). Another cluster ion with a polyethylene structure, [GaH(2)](n)(n-), was found in a second novel (RbGaH(2))(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.
authors.affiliation: Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Fahlquist
authors.forename: Dag
authors.initials: D
authors.lastname: Noréus
authors.forename: Samantha
authors.initials: S
authors.lastname: Callear
authors.forename: William I F
authors.initials: WI
authors.lastname: David
authors.forename: Björn C
authors.initials: BC
authors.lastname: Hauback