Stochastic search, fragmentation, electronic and reactivity properties of neutral and cationic hydrogenated Li6 clusters

• We calculated the lowest-energy isomer of neutral and cationic Li6Hn (n = 0–7) clusters.
• Stochastic search method based on the density functional theory was employed.
• The fragmentation channels of Li, H, LiH, H2 and Li2H2 forms were investigated.
• In neutral and cationic clusters is too high for the reversible hydrogen storage.
• The second isomer of neutral Li6H6 cluster is corresponding to a 3 × 2 × 2 compact structure.

In this study we investigated the lowest energy structures of neutral and cationic Li6Hn (n = 0–7) clusters using ab initio calculations based on DFT and CCSD(T) methods. We used the stochastic search method to obtain the global minimum on the potential energy surface of hydrogenated lithium clusters. For the lowest-energy isomers of the clusters, the relative stabilities, electronic and reactivity properties are presented depending on the binding energies, second energy difference, chemical hardness, chemical potential, softness, electrophilicity index, ionization potentials, electron affinities and HOMO–LUMO energy gaps. We also studied the fragmentation energies of neutral and cationic hydrogenated lithium clusters. In particular, the fragmentation energies of cationic clusters are compared with experimental data. The results are in good agreement with most available experimental findings.

We have reported the second isomer of neutral Li6H6 clusters, which very close to a 3 × 2 × 2 compact structure, is corresponding to one-quarter of a 3 × 3 × 3 compact lattice structure (Li14H13).Figure optionsDownload as PowerPoint slide