The scaling law of cluster sizes revisited: Clusters formed via coexpansion of a molecular and a rare gas species

Abstract

We report experimental measurements of cluster sizes formed from supersonic expansion of two different species based on the time-of-flight principle. Argon clusters containing aromatic molecules are ionized at 266 nm at a low laser intensity. A high voltage is used to accelerate the heavy cluster ions thereby increasing the sensitivity of a microchannel plate detector. Our measurements of argon clusters, neat molecular clusters, and molecular-Ar clusters, are all in qualitative agreement with results predicted from the scaling law, but the fitting exponents for the dependence of cluster sizes on both the stagnation pressure and temperature are different.