Pure Molecular Beam of Water Dimer

Abstract

Spatial separation of water dimer from water monomer and larger water-clusters through the electric deflector is presented. A beam of water dimer with $93\%$ purity and a rotational temperature of $1.5$K was obtained. Following strong-field ionization using a $35$fs laser pulse with a wavelength centered around $800$nm and a peak intensity of $10^{14}\text{W}/{\text{cm}}^2$ we observed proton transfer and $46\%$ of the ionized water dimer broke apart into a hydronium ion ${\text{H}}_3{\text{O}}^{+}$ and neutral OH.