Solvation shell dynamics of Na+ and Cl- ion pairs in selected water-DMSO mixtures
نویسندگان
چکیده
We have investigated the solvation shell dynamics of Na and Cl ion pairs in water DMSO mixtures of three compositions with xDMSO (mole fraction of DMSO) = 0.21, 0.35 and 0.48. Dynamical ion pair trajectories in these compositions are studied to analyze the diffusional behaviour of the solvent molecules in the primary and secondary solvation shells as well as the bulk solvent. As expected, the diffusivity of the primary solvation shells is smaller than the bulk. The insertion of solvent molecules in the region between the ion pairs during the ion pair separation process is analyzed from the classical ion pair molecular dynamics trajectories in these compositions of water DMSO mixtures. Contact ion pair; solvent separated ion pair; primary solvation shell; secondary solvation shell; residence times; diffusion coefficients; pair correlation functions; classical molecular dynamics; dynamical trajectories.
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