We study the hydrogen bond dynamics of solutions of LiBr and NaBr in isotopically diluted water (2% HDO:D2O) with femtosecond spectral hole-burning spectroscopy. We study the frequency fluctuations of the O−H stretch vibrations of the HDO molecules and observe spectral dynamics with time constants of 0.8 ± 0.1 ps and 4.3 ± 0.3 ps. The slow process we assign to the hydrogen bond fluctuations of the O−H···Br hydrogen bonds of the hydration shell of the Br anion. We find that the time scale of the hydrogen bond fluctuations of the hydration shell of Br is independent of the nature of the cation and the concentration.

doi.org/10.1021/jp902424u
J. Phys. Chem. A
Ultrafast Spectroscopy

Timmer, R.L.A, & Bakker, H.J. (2009). Hydrogen bond fluctuations of the hydration shell of the bromide anion. J. Phys. Chem. A, 113(21), 6104–6110. doi:10.1021/jp902424u