Molecular Dynamics Simulations of CO₂ Molecules in ZIF‐11 Using Refined AMBER Force Field

Abstract

Nonbonding parameters of AMBER force field have been refined based onab initiobinding energies of CO2–[C7H5N2]−complexes. The energy and geometry scaling factors are obtained to be 1.2 and 0.9 forεandσparameters, respectively. Molecular dynamics simulations of CO2molecules in rigid framework ZIF-11, have then been performed using original AMBER parameters (SIM I) and refined parameters (SIM II), respectively. The site-site radial distribution functions and the molecular distribution plots simulations indicate that all hydrogen atoms are favored binding site of CO2molecules. One slight but notable difference is that CO2molecules are mostly located around and closer to hydrogen atom of imidazolate ring in SIM II than those found in SIM I. The Zn-Zn and Zn-N RDFs in free flexible framework simulation (SIM III) show validity of adapting AMBER bonding parameters. Due to the limitations of computing resources and times in this study, the results of flexible framework simulation using refined nonbonding AMBER parameters (SIM IV) are not much different from those obtained in SIM II.

Structural single and multiple molecular adsorption of CO 2 and H 2 O in zeolitic imidazolate framework (ZIF) crystals

“…In contrast to Wongsinlatam and Remsungnen [36] who showed that both the Im-CO 2 and the Im-H 2 O orientations in Zinc imidazole were energetically similar, we have found that both solute molecule orientations and behaviors differ. This result can be related to the more Lewis acidic nature of the CH imidazole bond.…”

“…In all the cases, the smallest O CO2 -H imid distance has been found to be ~2.4 Å which is close to the data measured by Wongsinlatam and Remsungnen [36] for ZIF11. For a better understanding of the CO 2 surface adsorption in ZIFs systems, we made geometry optimizations of the H1 and H2 configurations of ZIF6.…”

Ab Initio and DFT Studies on CO2 Interacting with Znq+–Imidazole (q=0, 1, 2) Complexes: Prediction of Charge Transfer through σ‐ or π‐Type Models

“…Generally, the computed intermonomer distances for CO 2 @[Zn q + Im] are consistent with those measured for CO 2 within ZIFs. For instance, the distance between σ‐type CO 2 –Zn q + –Im complexes (≈2.5 Å) is close to the smallest O CO2 –H Im distance (≈2.4 Å) computed and measured for CO 2 –ZIFs . For π‐type interactions, a distance of approximately 3.2 Å was found between the C atom of the CO 2 molecule and the nearest aromatic ring in CO 2 –ZIF‐4, which is close to that computed here for CO 2 @[Zn 0 Im] a MI (Table ).…”

Modelling Gas Adsorption in Porous Solids: Roles of Surface Chemistry and Pore Architecture

“…However, this aspect will be studied by us in future, using methods such as hybrid GCMC/MD. [51][52][53][54][55] Configurations were visualized using VMD. 56…”