Computational study B3LYP interaction of molecular hydrogen [H₂] with <em>rccc</em> R-Pyg [4]arenes [R = methyl, fluoride] functionalized with Li⁺

Abstract

The interaction of molecular hydrogen [H2] with methyl- and fluoride-substituted rccc pirogallol[4]arenes functionalized with Li+ cations [Li-R-Pyg[4]Ar] was theoretically studied by means of DFT quantum-mechanical calculations at the B3LYP/6-311G (d,p) level of theory. In a first stage of the study, the stability of the Li+ cation within the cavity of the R-Pyg[4]arenes was analyzed by inspecting the local environment of the adsorbed ion and the total density as well as the electrostatic potential maps of the complexes. In a subsequent stage of the work, the optimal position of a H2 molecule in the cavity of the pure and lithium-functionalized R-Pyg[4]arenes was determined. Upon obtaining the equilibrium geometry, the BSSE-corrected binding energy of the various H2/R-Pyg[4]Ar complexes was calculated. The results showed that the sorption capacity of R-Pyg[4]arenes is significantly improved by the presence of the Li+ cation within their cavity.

Keywords

• Almacenamiento de hidrógeno
• pirogalol
• DFT
• capacidad de adsorción