Energetics during proton transfer process in hydrated zündel ion complex

Abstract

Zü ndel ion (H 5 O þ2 ) is one of the two important structures formed during the proton transfer process in aqueous system. This work reports microsolvation of Zü ndel ion using density functional theory based B3LYP method with aug-cc-pVTZ basis set. Interaction of Zü ndel ion with four water molecules in its first solvation shell is studied using many-body analysis approach. A change in many-body energies and their contribution to the binding energy of a complex during the proton transfer process from donor to acceptor water molecule in Zü ndel ion-4H 2 O complex is obtained. For the hydrated Zü ndel ion complex, the contribution from total two-body, three-body, fourbody, five-body, and relaxation energy to the binding energy is 84.7, 14, 6.87, 1.6, and 4%, respectively, at B3LYP/aug-cc-pVTZ level. Relaxation energy and total five-body energy have repulsive contribution to the binding energy of a hydrated Zü ndel ion complex. It is found that the relaxation energy and binding energy of a Zü ndel-4H 2 O complex is the maximum and minimum, respectively, when a shared proton is at equal distance from oxygen atom of donor and acceptor water molecules. A significant change in two-body, three-body, and four-body energies for which Zü ndel ion is one of the many-body terms is observed during the proton transfer process. A change in total two-body, total threebody, total four-body, and relaxation energy is about 2.6, 1.8, 0.4, and 1.1%, respectively, during the proton transfer process. A change in two-body, three-body, and four-body interaction energies between water molecules is very small during the proton transfer process.

Mechanism of proton transport in water clusters and the effect of electric fields: A DFT study

“…We obtained the binding energy, which is defined as the energy difference between the optimized dimer and two optimized monomers, of 19.7 kJ/mol which is in good agreement with literature value [30][31][32][33]. In addition, B3LYP was used extensively in previous studies of proton transfer in water environment [34][35][36]. Therefore, the choice of this method seems reasonable for the balance between computing cost and accuracy.…”

The electric double layer at metal-water interfaces revisited based on a charge polarization scheme

“…In this study, we will particularly consider electrochemical interfaces between Pt(111) and a water film which additionally contains ions such as hydronium and hydroxyl ions [34][35][36][37][38][39][40][41]. By performing AIMD simulations we will elucidate the structure of the electric double layer and derive the corresponding electrode potential.…”

Assessing Many-Body Effects of Water Self-Ions. I: OH–(H2O)n Clusters

“…It is known that for systems whose MBEs converge quickly knowledge about molecular clusters can be systematically extended to bulk systems. Many studies have been reported in the literature investigating OH – (H 2 O) n and H 3 O + (H 2 O) n clusters using both theoretical − and experimental ,,− approaches. However, a rather small fraction of the theoretical work investigated many-body effects in these clusters. ,,,,,,− As a first step toward a quantitative assessment of many-body effects of water self-ions in aqueous systems, we report here an analysis of OH – –water interactions in low-energy isomers of OH – (H 2 O) n clusters, with n ≤ 5.…”