Theoretical and experimental research on the solvation shell microstructure in saturated NaCl solution

Abstract This study determines the thermodynamically most probable microstructures (first solvation shell configuration) of saturated NaCl solution via integrated experimental-computational approaches. Experimental XRD analysis reveals distinct structural features distinguishing saturated NaCl solution from pure water. DFT simulations employing the explicit/implicit solvation model identify M(H 2 O) 6 (M = Na + , Cl − ) clusters as stable first solvation shells, confirmed by both geometric and energetic analyses. Crucially, simulated XRD patterns derived from the first solvation shells show excellent agreement with experimental data in peak positions, plateau regions, and relative intensities, so that the rationality and accuracy of the model have been fully verified.