Theoretical studies of copper clusters

Courtney Marie Sams

Published Jan 1, 2013• 0 citations

Abstract

We introduce an experimental platform designed around a thermo-mechanical helium fountain, which is aimed at investigating spectroscopy and dynamics of atoms and molecules in the superfluid, and at its vapor interface.Laser ablation of copper, efficient cooling and transport of Cu and Cu 2 through helium vapor (1.5 K < T < 20 K), formation of linear and T-shaped Cu 2 -He complexes, and their continuous evolution into large Cu 2 -He n clusters and droplets, are among the processes that are illustrated.Reflection is the dominant quantum scattering channel of translationally cold copper atoms (T = 1.7 K) at the fountain interface.Cu 2 dimers mainly travel through the fountain unimpeded.However, the conditions of fountain flow and transport of molecules can be controlled to demonstrate injection, and in particular injection into a non-divergent columnar fountain with a plug velocity of ca. 1 m/s.The experimental observables are interpreted with the aid of bosonic density functional theory calculations and ab initio interaction potentials.

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