Structures of the strontium and barium dodecahydro-closo-dodecaborates

The structures of the anhydrous alkaline-earth-metal dodecahydro-closo-dodecaborates, SrB12H12 and BaB12H12, were determined by X-ray and neutron powder diffraction methods corroborated by a combination of neutron vibrational spectroscopic data and density-functional-theory-based phonon calculations. Both compounds possess the same novel trigonal structure with P31c space group symmetry, which appears to represent the most stable arrangement of alkaline-earth cations and dodecahydro-closo-dodecaborate anions for cations above a certain size. Published by Elsevier B.V.