Hydrogen bond fluctuations of the hydration shell of the bromide anion.
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.
Timmer
R L A
RL
FOM-Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands. r.timmer@amolf.nl
Bakker
H J
HJ