Controlling Thermal Stability and Volatility of Organogold(I) Compounds for Vapor Deposition with Complementary Ligand Design

We compare and contrast the volatility and thermal stability of a family of twelve organometallic gold(I) compounds using a combination of X-ray crystallography, thermogravimetric analysis (TGA), and density functional theory (DFT) techniques. Pentafluorophenyl is used as a new ligand for vapor deposition which produces rather low volatility, but very thermally stable compounds when combined with PMe₃ and N,N'-di-tert-butylimidazolidin-2-ylidene. We introduce a precursor figure of merit that can be used to rank precursor usefulness. Using DFT, we find a linear correlation between Au-L bond strength and thermal stability, which demonstrates the power of computational techniques to predict successful synthetic targets for future precursor design studies.