Structure dynamics of the proton in liquid water probed with terahertz time-domain spectroscopy.


We study the hydration of protons in liquid water using terahertz time-domain spectroscopy and polarization-resolved femtosecond midinfrared pump-probe spectroscopy. We observe that the addition of protons leads to a very strong decrease of the dielectric response of liquid water that corresponds to 19+/-2 water molecules per dissolved proton. This… (More)