Encapsulation of Hydrogen Molecules in C₅₀ Fullerene: An ab Initio Study of Structural, Energetic, and Electronic Properties of H₂@C₅₀ and 2H₂@C₅₀ Complexes

Abstract

Various DFT functionals, including those containing long-range interactions and dispersion, together with HF and MP2 theoretical methods, were used to identify the number of H2 molecules that can be encapsulated inside a C50 cage. It is demonstrated that the 2H2@C50 complex is thermodynamically unstable based on its positive complexation energy. Some discrepancies, however, were found with respect to the stability of the H2@C50 complex. Indeed, SVWN5, PBEPBE, MP2, B2PLYP, and B2PLYPD calculations confirmed that the H2@C50 complex is thermodynamically stable, while HF, BP86, B3LYP, BHandHLYP, LC–wPBE, CAM–B3LYP, and wB97XD showed that this complex is thermodynamically unstable. Nevertheless, examination of strain and dispersion energies further supported the fact that one H2 molecule can indeed be encapsulated inside the C50 cage. Other factors, such as the host–guest interactions and bond dissociation energy, were analyzed and discussed.

Interexcited State Photophysics I: Benchmarking Density Functionals for Computing Nonadiabatic Couplings and Internal Conversion Rate Constants

“…This list is shown in Table , and is discussed below. In looking through many DFT benchmarking works, ,− ,,,− ,, we feel the list of chosen density functionals is of sufficient quality such that a wide enough range of functionals is encapsulated and examined.…”

“…Benchmarking DFT and DFT-based methods is common practice, with focused applications ranging between noble-gas chemistry, prediction of optical properties, − structural or lattice physics, − hydrogen storage, nuclear magnetic resonance and magnetic properties, , frequency analysis, thermochemical and noncovalent interactions, , to even “mindless” quality control and tests of robustness. ,− However, to the best of our knowledge, no study currently exists that benchmarks how NACMEs differ between various density functionals. In particular, how each functional, or even how different classes of functionals, alter NACMEs is not discussed anywhere in the literature.…”

Reversible Hydrogen Storage in a Superalkali NLi4-Decorated Biphenylene Monolayer: Insights from a First-Principles Study

“…Furthermore, the latest guidelines of the Department of Energy (DOE) necessitate that storage systems achieve a gravimetric density of 5.5 wt % under practical temperature and pressure conditions . Numerous efforts are being made in pursuit of this goal, utilizing a variety of methodologies to develop suitable hydrogen storage materials. , …”

A Computational Insight on the Effect of Encapsulation and Li Functionalization on Si12C12 Heterofullerene for H2 Adsorption: A Strategy for Effective Hydrogen Storage

“…10 Over the past few decades, several hydrogen storage techniques, including conventional and material-based storage methods, have been investigated. Among these material-based storage systems, nanocages, 11 nanoclusters, 12 fullerenes, 13 and metal-encapsulated heterofullerenes 14 have recently attracted significant attention as hydrogen storage templates with promising results. The establishment of a new hydrogenbased economy is significantly dependent on the ability to discover materials that can reversibly store hydrogen with a high gravimetric density and can be operated at ambient temperatures and pressure conditions.…”