Polarization Effects in Aqueous and Nonaqueous Solutions

Marenich, Aleksandr V.; Olson, Ryan M.; Chamberlin, Adam C.; Cramer, Christopher J.; Truhlar, Donald G.

doi:10.1021/ct7001539

Cited by 64 publications

(76 citation statements)

References 136 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Charge transfer has been implicated in a wide range of biophysical solvation problems 79 and has been previously observed in DFT simulations 66 and quantum chemical studies. 71,80,81 It is possible that the over-polarized ions observed in the AMOEBA model somehow mimic this charge transfer effect in an average way, but further work is necessary to quantify the relation of the classical models to the more realistic quantum calculations (the results for the small N cases in Figure 8 suggest that some of the essential physics is missing from the multipole representation, however). Since most models used to study the surface affinity of anions to the water liquid-vapor interface have employed no electrostatic damping, or limited versions as in the AMOEBA model, these issues should be revisited in modeling the specific ion effects.…”

Section: Summary and Discussionmentioning

confidence: 99%

“…The observation of significant charge transfer is consistent with the previous CPMD study by Dal Peraro and co-workers 66 and electronic structure calculations on anions in water. 71 Rashin et al 72 applied a different charge partitioning scheme and concluded that charge transfer in ion-water clusters is not as significant as the results discussed above. In order to analyze the differences between the ChelpG and QTAIM estimates of charge transfer observed in Figure 6, configurations were extracted from the AMOEBA simulations for clusters with N = 1 − 4 waters.…”

Section: B Ion and Water Dipole Moments And Charge Transfermentioning

confidence: 95%

See 1 more Smart Citation

Polarization and charge transfer in the hydration of chloride ions

Zhao

Rogers

Beck

2010

The Journal of Chemical Physics

View full text Add to dashboard Cite

A theoretical study of the structural and electronic properties of the chloride ion and water molecules in the first hydration shell is presented. The calculations are performed on an ensemble of configurations obtained from molecular dynamics simulations of a single chloride ion in bulk water. The simulations utilize the polarizable AMOEBA force field for trajectory generation, and MP2-level calculations are performed to examine the electronic structure properties of the ions and surrounding waters in the external field of more distant waters. The ChelpG method is employed to explore the effective charges and dipoles on the chloride ions and first-shell waters. The Quantum Theory of Atoms in Molecules (QTAIM) is further utilized to examine charge transfer from the anion to surrounding water molecules. The clusters extracted from the AMOEBA simulations exhibit high probabilities of anisotropic solvation for chloride ions in bulk water. From the QTAIM analysis, 0.2 elementary charges are transferred from the ion to the first-shell water molecules. The default AMOEBA model overestimates the average dipole moment magnitude of the ion compared with the estimated quantum mechanical value. The average magnitude of the dipole moment of the water molecules in the first shell treated at the MP2 level, with the more distant waters handled with an AMOEBA effective charge model, is 2.67 D. This value is close to the AMOEBA result for first-shell waters (2.72 D) and is slightly reduced from the bulk AMOEBA value (2.78 D). The magnitude of the dipole moment of the water molecules in the first solvation shell is most strongly affected by the local water-water interactions and hydrogen bonds with the second solvation shell, rather than by interactions with the ion.

show abstract

Section: Summary and Discussionmentioning

confidence: 99%

Section: B Ion and Water Dipole Moments And Charge Transfermentioning

confidence: 95%

Polarization and charge transfer in the hydration of chloride ions

Zhao

Rogers

Beck

2010

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…Mixed solvation models explicitly include chemically important solute-solvent interactions and account for charge transfer to the solvent that are particularly important for hydrated transition-metalion complexes. [73][74][75][76] The use of mixed cluster/continuum solvation models has been the subject of some criticisms, 77 including the incorrect orientations of water molecules near the dielectric boundary and the accurate evaluation of the entropic effects for the explicit water molecules. The first problem can be alleviated by the addition of a full first or second solvation shell.…”

Section: A Mixed Cluster/continuum Model For Transition Metal Ion Commentioning

confidence: 99%

Computational Study of Copper(II) Complexation and Hydrolysis in Aqueous Solutions Using Mixed Cluster/Continuum Models

2009

View full text Add to dashboard Cite

We use density functional theory (B3LYP) and the COSMO continuum solvent model to characterize the structure and stability of the hydrated Cu(II) complexes [Cu(MeNH 2 2-x (x ) 1-3) as a function of metal coordination number (4-6) and cluster size (n ) 4-8, 18). The small clusters with n ) 4-8 are found to be the most stable in the nearly square-planar four-coordinate configuration,, which is three-coordinate. In the presence of the two full hydration shells (n ) 18), however, the five-coordinate square-pyramidal geometry is the most favorable for Cu (MeNH 2 ) 2+ (5, 6) and Cu(OH) + (5, 4, 6), and the four-coordinate geometry is the most stable for Cu(OH) 2 (4, 5) and Cu(OH) 3 -(4). (Other possible coordination numbers for these complexes in the aqueous phase are shown in parentheses.) A small energetic difference between these structures (0.23-2.65 kcal/mol) suggests that complexes with different coordination numbers may coexist in solution. Using two full hydration shells around the Cu 2+ ion (18 ligands) gives Gibbs free energies of aqueous reactions that are in excellent agreement with experiment. The mean unsigned error is 0.7 kcal/mol for the three consecutive hydrolysis steps of Cu 2+ and the complexation of Cu 2+ with methylamine. Conversely, calculations for the complexes with only one coordination shell (four equatorial ligands) lead to a mean unsigned error that is >6.0 kcal/mol. Thus, the explicit treatment of the first and the second shells is critical for the accurate prediction of structural and thermodynamic properties of Cu(II) species in aqueous solution.

show abstract

“…[24,25] The first set of methods is routinely performed nowadays, but for our systems in which the solvent participates actively, a single optimized structure does not resemble the configurational distribution at finite temperature. First-principle molecular dynamics simulations are often restricted by short simulation times.…”

mentioning

confidence: 99%