Laser vaporization of solids into an inert gas: A measure of high-temperature cluster stability

We have studied the effects of an inert cooling gas on laser vaporization of solid sodium chloride. The unicluster decay cascades that follow the vaporizing laser pulse are rapidly quenched in helium or argon gas, generating cluster ions whose relative populations reflect their high-temperature stabilities against decay. Cluster production and thermalization are shown to occur in less than 15 ns. Abundance measurements of [Na(NaCl${)}_{\mathrm{n}}$ ${]}^{+}$ ions (n=1–157) confirm that surface steps are the most stable additions to a cuboid base lattice.