Metallophilicity-Driven Dynamic Aggregation of a Phosphorescent Gold(I)–Silver(I) Cluster Prepared by Solution-Based and Mechanochemical Approaches

We
observed an unusual reversible aggregation process showing stimuli-responsive
structural dynamics and optical changes attributed to the formation
of a sandwich-like Au3–Ag–Au3 cluster,
which can be synthesized through both solution and mechanochemical
methods. Unlike many other heteronuclear gold–silver clusters,
the affinity of two cyclic Au3 complexes and a AgI ion is solely bound by ligand unsupported Au–Ag bonding.
The assembly/disassembly behavior, further forming nanoaggregates,
is controllable by adjusting the concentration of the solution. In
the solid state, the insertion of AgI ion can be implemented
through a mechanochemical approach, accompanied by visual color changes
and reversible luminochromism. Furthermore, an uncommon solid–liquid
extraction is demonstrated, showing the uniqueness of this labile
Au–Ag metallophilicity and hinting at the possibility of manipulating
a bonding process through a heterogeneous route.