Complexes of gold and imidazole formed in helium nanodroplets

Abstract

We have studied complexes of gold atoms and imidazole (C${}_3$N${}_2$H${}_4$, abbreviated Im) produced in helium nanodroplets. Following the ionization of the doped droplets we detect a broad range of different Au${}_m$Im${}_n^{+}$ complexes, however we find that for specific values of $m$ certain $n$ are "magic" and thus particularly abundant. Our density functional theory calculations indicate that these abundant clusters sizes are partially the result of particularly stable complexes, e.g. AuIm${}_2^{+}$, and partially due to a transition in fragmentation patterns from the loss of neutral imidazole molecules for large systems to the loss of neutral gold atoms for smaller systems.

7 pages, 9 figures, published in Physical Chemistry Chemical Physics