Rapid isotopic exchange reveals the solution-state dynamics existing in nanoparticles, very similar to that in H2O and D2O.

A selenolate-protected Ag−Pd alloy cluster was synthesized using a one-pot solution-phase route. The crude product upon chromatographic analyses under optimized conditions gave three distinct clusters with unique optical features. One of these exhibits a molecular peak centered at m/z 2839, in its negative ion mass spectrum assigned to Ag 5 Pd 4 (SePh) 12 − , having an exact match with the corresponding calculated spectrum. Tandem mass spectrometry of the molecular ion peak up to MS 9 was performed. Complex isotope distributions in each of the mass peaks confirmed the alloy composition. We find the Ag 3 Pd 3 − core to be highly stable. The composition was further supported by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. SECTION: Physical Processes in Nanomaterials and