Water solubility Monte Carlo simulation

X-ray and neutron diffraction methods and EXAFS spectroscopy are very useful in getting structural information of solvated ions. These methods, combined with molecular dynamics and Monte Carlo simulations, have been used extensively to study the structures of hydrated ions in water. Detailed results can be found in the review by Ohtaki and Radnai [17]. The structural study of solvated ions in lion-aqueous solvents has not been as extensive, partly because the low solubility of electrolytes in 11011-aqueous solvents limits the use of X-ray and neutron diffraction methods that need electrolyte of -1 M. However, this situation has been improved by EXAFS (applicable at -0.1 M), at least for ions of the elements with large atomic numbers, and the amount of data on ion-coordinating atom distances and solvation numbers for ions in non-aqueous solvents are growing [15 a, 18]. For example, according to the X-ray diffraction method, the lithium ion in for-mamide (FA) has, on average, 5.4 FA molecules as nearest neighbors with an... 

Marin-Rimoldi, E., Shah, J.K., Maginn, E.J. Monte Carlo simulations of water solubility in ionic liquids a force field assessment. Eluid Phase Equilib. (2015). doi 10.1016/j.fluid.2015. 07.007... 

Monte Carlo simulations (Lai and Binder 1992). Figure 6.11 shows scanning force microscopy images of an end-grafted layer of a water-soluble polymer, dextran, which in water appears as a uniform layer, but, after the addition of a poor solvent, propanol, develops lateral structure (Frazier et al. 1997). As the grafting density is increased yet further the homogeneous, layer structure is expected once again to become stable. 

Molecular sciences look for explanations of macroscopic properties, e.g., solubility, from the microscopic properties of matter. Statistical mechanics is one of such disciplines, which hnks those two pictures through the probabilistic treatment of particle ensembles. The application of Kirkwood s continuum solvent approach to nondissociating fluids resulted in a variety of simulation techniques. Applications of such techniques to study phase equilibria have been reported widely in literature [1-10]. Although some simple hydrocarbons can nowadays be reasonably well described by molecular modeling (molecular dynamics and Monte Carlo simulations), water and especially water mixtures, still represent challenges for such simulations techniques despite 30 years of active parameterization of appropriate force-fields. This is due to the extremely strong and complicated electrostatic and hydrogen-bond interactions. 

Molecular simulations have been used to obtain thermodynamic properties and phase equilibria data of ionic liquid systems (i) Monte Carlo simulation techniques were employed to predict the solubility of gases and water in ionic liquids and (ii) molecular dynamics simulations were used to investigate the solvation dynamics of water and various organics in ionic liquids. ... 

To finalize the development of the aqueous CO2 force field parameters, the C02 model was used in free energy perturbation Monte Carlo (FEP/MC) simulations to determine the solubility of C02 in water. The solubility of C02 in water is calculated as a function of temperature in the development process to maintain transferability of the C02 model to different simulation techniques and to quantify the robustness of the technique used in the solubility calculations. It is also noted that the calculated solubility is based upon the change in the Gibbs energy of the system and that parameter development must account for the entropy/enthalpy balance that contributes to the overall structure of the solute and solvent over the temperature range being modeled [17]. 

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