In a recent Letter by Laenen and Thaller [Chem. Phys. Lett. 349 (2001) 442], results on the vibrational lifetime of aqueous salt solutions (LiCl, NaCl, KCl, or NaI) were presented. It was reported that the vibrational lifetime depends on the nature of the cation, and not on that of the anion. In this Comment, we present experimental results that show that the claims by Laenen and Thaller are wrong, and that the vibrational lifetime is influenced strongly by the anion, and only weakly by the cation.
Chem. Phys. Lett.
Ultrafast Spectroscopy

Kropman, M. F., & Bakker, H. (2002). Comment on: Water in the vicinity of solvated ions: modified dynamical and structural water properties resolved by sub-picosecond IR-spectroscopy by R. Laenen and A. Thaller. Chem. Phys. Lett., 362, 349–352. doi:10.1016/s0009-2614(02)01036-9