Synthesis, separation, and characterization of polymers from gold monolayer protected clusters

This work details the advances made in the synthesis, separation, and characterization of small-chain gold monolayer protected cluster (MPC) polymers. Particles of 25 gold atoms (exhibiting molecule-like electronic behavior) or 140 gold atoms (showing electronic properties between those of molecular and bulk gold) were used to allow investigation of changes to these phenomena with MPC polymer assembly. Two classes of coupling chemistry, dithiol linkers and carbodiimide ester or amide formation, have been employed to synthesize these MPC polymers. Matrix assisted laser desorption ionization mass spectrometry has been used to aid in the identification of mixed monolayer starting materials, as well as to search for direct evidence of MPC assemblies. High performance reverse phase liquid chromatography and size exclusion chromatography have been used to separate complex mixtures of reaction products and isolate MPC polymers. TEM of these collected fractions has allowed imaging of MPC polymer assemblies.