Hydrated Sodium Ion Clusters [Na+(H2O)n (n = 1–6)]: An ab initio Study on Structures and Non-covalent Interaction

Wang, Pengju; Shi, Ruili; Su, Yan; Tang, Lingli; Huang, Xiaoming; Zhao, Jijun

doi:10.3389/fchem.2019.00624

Cited by 32 publications

(25 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The resulting F – (H 2 O) 2,4 clusters are asymmetric as opposed to the symmetric Na + (H 2 O) 2,4 clusters. The geometries of Na + (H 2 O) 2,4,5 and F – (H 2 O) 3–5 clusters are similar compared to those found in other computational studies. , …”

Section: Resultssupporting

confidence: 82%

Heterogeneous Ion-Induced Nucleation of Water and Butanol Vapors Studied via Computational Quantum Chemistry beyond Prenucleation and Critical Cluster Sizes

et al. 2023

View full text Add to dashboard Cite

Water and butanol are used as working fluids in condensation particle counters, and condensation of a single vapor onto an ion can be used as a simple model system for the study of ion-induced nucleation in the atmosphere. Motivated by this, we examine heterogeneous nucleation of water (H 2 O) and n-butanol (BuOH) vapors onto three positively (Li + , Na + , K + ) and three negatively charged (F − , Cl − , Br − ) ions using classical nucleation theory and computational quantum chemistry methods. We study phenomena that cannot be captured by Kelvin−Thomson equation for small nucleation ion cores. Our quantum chemistry calculations reveal the molecular mechanism behind ion-induced nucleation for each studied system. Typically, ions become solvated from all sides after several vapor molecules condense onto the ion. However, we show that the clusters of water and large negatively charged ions (Cl − and Br − ) thermodynamically prefer the ion being migrated to the cluster surface. Although our methods generally do not show clear sign-preference for ion−water nucleation, we identified positive sign-preference for ion− butanol nucleation caused by the possibility to form stabilizing hydrogen bonds between butanol molecules condensed onto a positively charged ion. These bonds cannot form when butanol condenses onto a negatively charged ion. Therefore, we show that ion charge, its sign, as well as vapor properties have effects on the prenucleation and critical cluster/droplet sizes and also on the molecular mechanism of ion-induced nucleation.

show abstract

Section: Resultssupporting

confidence: 82%

Heterogeneous Ion-Induced Nucleation of Water and Butanol Vapors Studied via Computational Quantum Chemistry beyond Prenucleation and Critical Cluster Sizes

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Here, we argue that there indeed is a significant change in the electronic structure of Na + in the presence of water that can explain why MQC calculations with pairwise additive pseudopotentials yield an overly blue-shifted spectrum for aqueous electron–cation contact pairs. Several groups, using both ab initio , and polarizable classical MD methods, have noted that when sodium cations are dissolved in water, the first solvation shell waters donate charge to the cation’s empty 3s atomic orbital. The net result is that the effective charge on aqueous Na + decreases from 1.0 e in the gas phase to ∼0.9 e in aqueous solution .…”

Section: Results and Discussionmentioning

confidence: 99%

Hydrated Electrons in High-Concentration Electrolytes Interact with Multiple Cations: A Simulation Study

2022

View full text Add to dashboard Cite

Experimental studies have demonstrated that the hydrated electron’s absorption spectrum undergoes a concentration-dependent blue-shift in the presence of electrolytes such as NaCl. The blue-shift increases roughly linearly at low salt concentration but saturates as the solubility limit of the salt is approached. Previous attempts to understand the origin of the concentration-dependent spectral shift using molecular simulation have only examined the interaction between the hydrated electron and a single sodium cation, and these simulations predicted a spectral blue-shift that was an order of magnitude larger than that seen experimentally. Thus, in this paper, we first explore the reasons for the exaggerated spectral blue-shift when a simulated hydrated electron interacts with a single Na+. We find that the issue arises from nonpairwise additivity of the Na+–e– and H2O–e– pseudopotentials used in the simulation. This effect arises because the solvating water molecules donate charge into the empty orbitals of Na+, lowering the effective charge of the cation and thus reducing the excess electron–cation interaction. Careful analysis shows, however, that although this nonpairwise additivity changes the energetics of the electron–Na+ interaction, the forces between the electron, Na+, and water are unaffected, so that mixed quantum/classical (MQC) simulations produce the correct structure and dynamics. With this in hand, we then use MQC simulations to explore the behavior of the hydrated electron as an explicit function of NaCl salt concentration. We find that the simulations correctly reproduce the observed experimental spectral shifting behavior. The reason for the spectral shift is that as the electrolyte concentration increases, the average number of cations simultaneously interacting in contact pairs with the hydrated electron increases from 1.0 at low concentrations to ∼2.5 near the saturation limit. As the number of cations that interact with the electron increases, the cation/electron interactions becomes slightly weaker, so that the corresponding Na+–e– distance increases with increasing salt concentration. We also find that the dielectric constant of the solution plays little role in the observed spectroscopy, so that the electrolyte-dependent spectral shifts of the hydrated electron are directly related to the concentration-dependent number of closely interacting cations.

show abstract

“…For the pure NaOH electrolyte solution, the first solvation shells of Na + are dominated by dipolar water molecules to form [Na(OH 2 ) 6–7 ] + , as revealed by the sharp peak at 2.35 Å in Figure a. Generally, Na + should be solvated by about 5.5 ± 0.5 water molecules in dilute Na + solutions . However, the high concentration of NaOH here leads to more H 2 O molecules (about 6.6 H 2 O) bound to Na + .…”

Section: Resultsmentioning

confidence: 87%

“…For the pristine water solution, water molecules interact with each other through weak hydrogen bonds (H–O···H). Apparently, these free water molecules with high activity can easily generate hydrogen through side reactions with Al. , With regards to the NaOH electrolyte, Na + ions tend to form the first solvation layer with several water molecules through ion–dipole (Na···O–H) bonds . Moreover, these isolated [Na(OH 2 ) n ] + clusters are further surrounded by free water molecules, forming a loose second solvation layer.…”

Section: Resultsmentioning

confidence: 99%

Electrolyte Solvation Structure Regulation Promotes Aluminum–Air Batteries to Approach Theoretical Discharge Capacity

et al. 2023

View full text Add to dashboard Cite

Aluminum−air batteries (AABs) feature high energy density and no limitations for charging facilities but suffer from severe self-corrosion reactions. Suppressing the side reaction between water and aluminum is the fundamental strategy to boost AAB performance. Herein, we first disclose that addition of sodium formate (HCOONa) can largely remold the solvation structure of the classic NaOH electrolyte and greatly reduce the amount of free water, thus constructing AABs close to their theoretical capacity. Ab initio molecular dynamics simulations show that multiple Na + and H 2 O form hydrated Na + ion clusters [Na m (OH 2 ) 7m ] m+ in the HCOONa−NaOH electrolyte. Meanwhile, HCOO − enters the first solvation layer of Na + and forms a "stable triangle" with Na + and H 2 O. The coordination network formed by Na + , H 2 O, and HCOO − results in a very low level of free water. Moreover, HCOO − further forms a self-assembled passivation layer on the Al surface. As such, the self-corrosion rate of Al in the HCOONa-based electrolyte is drastically reduced. More encouragingly, the ultrahigh capacity (2767 mAh g −1 ) delivered by AABs using the hybrid electrolyte reaches 92.9% of its theoretical value, concurrently achieving a high energy density of 3702 Wh kg −1 . This work paves the way for constructing durable AABs through an electrolyte regulation strategy.Article pubs.acs.org/JPCC

show abstract

Hydrated Sodium Ion Clusters [Na+(H2O)n (n = 1–6)]: An ab initio Study on Structures and Non-covalent Interaction

Cited by 32 publications

References 72 publications

Heterogeneous Ion-Induced Nucleation of Water and Butanol Vapors Studied via Computational Quantum Chemistry beyond Prenucleation and Critical Cluster Sizes

Heterogeneous Ion-Induced Nucleation of Water and Butanol Vapors Studied via Computational Quantum Chemistry beyond Prenucleation and Critical Cluster Sizes

Hydrated Electrons in High-Concentration Electrolytes Interact with Multiple Cations: A Simulation Study

Electrolyte Solvation Structure Regulation Promotes Aluminum–Air Batteries to Approach Theoretical Discharge Capacity

Contact Info

Product

Resources

About