Abstract
We identify a class of novel low energy phases of the hydrogen storage material by using the ab initio minima hopping crystal structure prediction method. These phases are, unlike previous predictions and known structures of similar materials, characterized by polymeric networks consisting of Al atoms interlinked with H atoms. The most stable structure is a layered ionic crystal with symmetry, and it has lower free energy than the previously reported structure over a wide range of temperatures. Furthermore, we carry out x-ray diffraction, phonon, and band-structure analysis in order to characterize this phase. Its experimental synthesis would have profound implications for the study of dehydrogenation and rehydrogenation processes and the stability problem of for hydrogen storage applications.
- Received 18 January 2012
DOI:https://doi.org/10.1103/PhysRevLett.108.205505
© 2012 American Physical Society