Exploring CO₂@sI Clathrate Hydrates as CO₂Storage Agents by Computational Density Functional Approaches

The formation of specific clathrate hydrates and their transformation at given thermodynamic conditions depends on the interactions between guest molecule/s host water lattice. Understanding structural stability is essential to control structure-property relations involved in different technological applications. Thus, energetic aspects relative CO2@sI hydrate are investigated through computation underlying interactions, dominated by hydrogen bonds van der Waals forces, from first-principles electronic structure approaches. evaluated combining bottom-up top-down Guest-free CO2 guest-filled aperiodic cages, up gradually occupation entire sI periodic unit cells were considered. Saturation, cohesive binding energies for systems determined employing a variety density functionals performance assessed. dispersion corrections non-covalent found be important stabilization energies, with encapsulation into guest-free/empty cage/lattice being always an energetically favorable process most studied. PW86PBE functional XDM or D3(BJ) predicts lattice constant accord experimental values available, simultaneously provides reliable description guest-host crystal, as well energetics its progressive single cage occupancy process. It has been that preferential orientation large crystal cages stabilizing effect hydrate, concluding favored either considering individual building block complete cell crystal. Such benchmark methodology cross-check studies benefit new data-driven model research providing high-quality training information, insights indicate factors governing structure-driven stability, triggering further investigations controlling these promising long-term storage materials.