Modelling the interaction of molecular hydrogen with lithium-doped hydrogen storage materials

Density functional theory (DFT) and ab initio methods are used to investigate the interaction of one, two and three hydrogen molecules with Li+-doped benzene, a model for lithium-doped carbon-based and metal organic framework materials. M05-2X is found to be the best DFT method considered, reproducing MP2 and CCSD(T) H2 binding energies to Li+-doped benzene. The M05-2X results also agree with H2 binding energies previously obtained in an extended model of Li atom-doped MOF-5. These calculations suggest H2 binding in Li-doped materials is, primarily, a local interaction, implying that model compounds can be used to describe these systems.