Impact of metal-alkoxide functionalized linkers on H₂ binding: A density functional study

Highlights: • Interaction between magnesium-alkoxide modified organic linker and H₂ investigated. • AIM, NBO and LMO-EDA employed to show the interactions between Mg and H₂. • B.E. of H₂ does not change considerably by increasing the aromatic ring size. • Linker containing 6-member alkoxide ring bind H₂ strongly than 5-member analogue. The effect of metal-alkoxide functionalization of different organic linkers on the H₂ binding is investigated employing DFT approach. While analyzing the H₂ binding interaction of magnesium-alkoxide modified benzene, naphthalene, anthracene and pyrene linkers, we find their comparable affinity toward H₂ molecules. Six-member alkoxide ring containing naphthalene and pyrene systems interact with the H₂ molecules in a comparatively better way than their five-member analogues. AIM, NBO and LMO-EDA analyses have been performed to comprehend the bonding nature between Mg center and the H₂ molecules. Polarization along with the charge transfer interactions play significant role in stabilizing the systems.