Theoretical insights into the dimerization mechanism of aluminum species at two different pH conditions

X, Jin; Liao, Rongbao; Zhang, Ting; Li, Huiquan

doi:10.1016/j.ica.2021.120311

Cited by 6 publications

(5 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…39 Although the two types of dimeric species have slight energy differences under the fully solvated conditions, the transition reaction from di-μ 2 -hydroxo to μ 2 -oxo species can be greatly enhanced by a lack of solvation waters (e.g., under low water concentrations) and when countercations are present. 76 These computational results indicate that the two types of dimers, acting as a local molecular motif for the formation of higher order oligomers, may have different stabilities (or abundance) crossing the solution compositions presented in Figure 2. It is likely that the kinetically controlled di-μ 2 -hydroxo-bridged Al 2 (OH) 8…”

Section: Concentration-dependent Ion Structure Dynamics and Associati...mentioning

confidence: 79%

“…In light of these experimental observations, AIMD studies by Pouvreau et al, , and Jin et al confirmed that the two principal dimeric species in alkaline aluminate solutions are the μ 2 -oxo-bridged Al 2 O(OH) 6 2– dimer and di-μ 2 -hydroxo-bridged Al 2 (OH) 8 2– dimer (see Figure ). These simulations in the dilute limit predict that the di-μ 2 -hydroxo-bridged Al 2 (OH) 8 2– forms more readily kinetically due to reorientation/bridging of the aluminate OH – ligands, but the μ 2 -oxo-bridged Al 2 O(OH) 6 2– is more favored thermodynamically.…”

Section: Concentration-dependent Ion Structure Dynamics and Associati...mentioning

confidence: 82%

“…When ion-pairing interactions are presented between an alkali-metal cation and either of the two dimers, the μ 2 -oxo-bridged Al 2 O(OH) 6 2– is also energetically favored with respect to the di-μ 2 -hydroxo-bridged Al 2 (OH) 8 2– . Although the two types of dimeric species have slight energy differences under the fully solvated conditions, the transition reaction from di-μ 2 -hydroxo to μ 2 -oxo species can be greatly enhanced by a lack of solvation waters (e.g., under low water concentrations) and when countercations are present . These computational results indicate that the two types of dimers, acting as a local molecular motif for the formation of higher order oligomers, may have different stabilities (or abundance) crossing the solution compositions presented in Figure .…”

Section: Concentration-dependent Ion Structure Dynamics and Associati...mentioning

confidence: 99%

See 2 more Smart Citations

Solution and Interface Structure and Dynamics in Geochemistry: Gateway to Link Elementary Processes to Mineral Nucleation and Growth

Wang

Yuan

Rampal

et al. 2021

Crystal Growth & Design

View full text Add to dashboard Cite

Our understanding of the process of mineral nucleation is starting to evolve from the solely thermodynamical aspects in classical nucleation theory toward a mechanistic study of reactions influenced by solvation structures of ions and their dynamics. A knowledge of how these atomic and molecular interactions respond to changing solution composition and/or the nature of an interface will form a fundamental foundation to understand rate-limiting reactions and processes for nucleation and growth. Here, we review recent advances from multidisciplinary experimental and computational approaches of the structure and dynamics of aqueous solutions and mineral–liquid interfaces that will influence rates of nucleation (and growth behavior) both homogeneously in aqueous solutions and heterogeneously at mineral–liquid interfaces. These processes include structure (and extent) of solute clustering, solvent degrees of freedom, and the presence of noninnocent charge-balancing ions, all of which can drive the selectivity and exert control over nucleation mechanisms. Similar controlling reactions can also occur at interfaces with the added complexities of how solute ions interact with and assemble on surface sites and use different mechanisms from bulk solutes, such as lateral solvent exchanges between distinct surface sites. To gain a predictive understanding of nucleation chemistry, we emphasize several key knowledge gaps that will need to be addressed in this field and highlight the importance of combining computations and experiments.

show abstract

Section: Concentration-dependent Ion Structure Dynamics and Associati...mentioning

confidence: 79%

Section: Concentration-dependent Ion Structure Dynamics and Associati...mentioning

confidence: 82%

Section: Concentration-dependent Ion Structure Dynamics and Associati...mentioning

confidence: 99%

See 1 more Smart Citation

Solution and Interface Structure and Dynamics in Geochemistry: Gateway to Link Elementary Processes to Mineral Nucleation and Growth

Wang

Yuan

Rampal

et al. 2021

Crystal Growth & Design

View full text Add to dashboard Cite

show abstract

“…Aluminum compounds, such as alumina, aluminum hydroxide, and aluminum sulfate, find diverse applications in electronic devices, heat insulation, and water treatment. − The sol–gel method is widely employed for the preparation of various aluminum products due to its simplicity, economic applicability, and wide range of applications. − Nanoscale aluminum particles gradually form through hydrolysis and polymerization reactions during the sol process. Despite numerous studies conducted on large polymeric species that exist stably in solution, such as AlO 4 Al 12 (OH) 24 (H 2 O) 12 7+ and Al 30 O 8 (OH) 56 (H 2 O) 24 18+ , the mechanisms behind the formation and growth of these aluminum clusters remain unclear. − Since aluminum oligomers are the basis for the formation of polymeric species, the study of aluminum oligomers, particularly the most fundamental aluminum monomers, contributes to revealing the formation process of polynuclear aluminum clusters and provides guidance for the preparation of aluminum-based materials. − …”

Section: Introductionmentioning

confidence: 99%

Ab Initio Molecular Dynamics Study of the Proton Transfer in Hydroxyl Ion-Induced Hydrolysis of Aluminum Monomers

Guo,

Xia,

Jiao

et al. 2023

J. Phys. Chem. B

View full text Add to dashboard Cite

The hydrolysis process of Al(H 2 O) 6 3+ induced by hydroxyl ions (OH − ) is significant to aluminum solution chemistry. Previous investigations of hydrolysis reactions have primarily relied on static calculations in an implicit solvent environment. Herein, we employ ab initio molecular dynamics (AIMD) to investigate the evolution process of Al(H 2 O) 6 3+ under various local alkaline conditions in an explicit solvent environment. Our work demonstrates the effect of solvent water in hydrolysis reactions. Specifically, the stepwise hydrolysis reaction induced by hydroxyl ions involves water wire compression and concerted proton transfers. Dehydration reactions occur when the number of hydroxyl ligands attached to the aluminum ion (Al 3+ ) equals or exceeds three. Moreover, the Al(H 2 O) n (OH) 3 species exhibit unique hydrolysis and dehydration reaction characteristics compared to other species. The geometrically stable aluminum monomers determined by AIMD are Al(H 2 O) 5 (OH) 1 2+ , Al(H 2 O) 4 (OH) 2 + , Al(H 2 O) 1 (OH) 3 , and Al(OH) 4 − . In addition, the topological analysis analyzes the interaction between Al 3+ and coordinated H 2 O in different configurations, indicating the weakest interaction appearing in Al(H 2 O) n (OH) 3 species.

show abstract

“…Focusing on divalent and multivalent cation dimer species, the electrostatic repulsion between cations is overcome by OH − and/ or O 2− bridges, plus the surrounding water/high dielectric media. Al 3+ dimers, which can be bridged reversibly by either two OH − or a single O 2− , have arguably received the most fundamental science studies due to their relevance to nuclear waste at high pH conditions [29][30][31][32][33][34] . In recent years divalent transition metal cation dimers and trivalent lanthanide dimers have become areas of technological significance 6,17,18 .…”

mentioning

confidence: 99%

Ab initio molecular dynamics free energy study of enhanced copper (II) dimerization on mineral surfaces

Leung

Greathouse

2022

Commun Chem

View full text Add to dashboard Cite

Understanding the adsorption of isolated metal cations from water on to mineral surfaces is critical for toxic waste retention and cleanup in the environment. Heterogeneous nucleation of metal oxyhydroxides and other minerals on material surfaces is key to crystal growth and dissolution. The link connecting these two areas, namely cation dimerization and polymerization, is far less understood. In this work we apply ab initio molecular dynamics calculations to examine the coordination structure of hydroxide-bridged Cu(II) dimers, and the free energy changes associated with Cu(II) dimerization on silica surfaces. The dimer dissociation pathway involves sequential breaking of two Cu2+-OH− bonds, yielding three local minima in the free energy profiles associated with 0-2 OH− bridges between the metal cations, and requires the design of a (to our knowledge) novel reaction coordinate for the simulations. Cu(II) adsorbed on silica surfaces are found to exhibit stronger tendency towards dimerization than when residing in water. Cluster-plus-implicit-solvent methods yield incorrect trends if OH− hydration is not correctly depicted. The predicted free energy landscapes are consistent with fast equilibrium times (seconds) among adsorbed structures, and favor Cu2+ dimer formation on silica surfaces over monomer adsorption.

show abstract

Theoretical insights into the dimerization mechanism of aluminum species at two different pH conditions

Cited by 6 publications

References 42 publications

Solution and Interface Structure and Dynamics in Geochemistry: Gateway to Link Elementary Processes to Mineral Nucleation and Growth

Solution and Interface Structure and Dynamics in Geochemistry: Gateway to Link Elementary Processes to Mineral Nucleation and Growth

Ab Initio Molecular Dynamics Study of the Proton Transfer in Hydroxyl Ion-Induced Hydrolysis of Aluminum Monomers

Ab initio molecular dynamics free energy study of enhanced copper (II) dimerization on mineral surfaces

Contact Info

Product

Resources

About