Exploration of the 2-dimensional π-d conjugated coordination polymer Cu-benzenehexathoil

Coordination polymers (CPs) are a type of atomically precise material that has long been an area of study for materials chemists. Recently, research has advanced with twodimensional conjugated CPs as detailed synthetic schemes are developed to create highly atomically ordered, large-area sheets. These 2D CPs consist of a planar organic ligand covalently bonded to a square planar metal ion which allows for π - d electron interactions. Those enable electron delocalization and may support exotic electronic characteristics to develop within the 2DCP. My project focuses on the CP Cu-benzenehexathiol (Cu-BHT). The first aim of my research was to standardize the synthesis of these materials so I could reliably create films with consistently high conductivities. After experimenting with different parameters, I could reproducibly create films with conductivities above 1000 S cm-1 which is standard for CVD synthesized Cu-BHT. I also explored the technique of Solvent Vapor Annealing (SVA) in the hopes of increasing the conductivities even more. The SVA experiments yielded films with lower conductivities in most cases. It may be worth exploring a potential healing mechanism that I theorized for methanol annealing on air-degraded films. My second aim was to explore the magnetic character of Cu-BHT after doping with magnetically active Fe2+. In the crystal lattice, Fe will replace Cu nodes and create magnetically active centers throughout the thin film. These paramagnetic nodes should allow the film to exhibit desirable magnetic properties which will be explored with Electron Spin Resonance (ESR). I was able to successfully synthesize doped films of up to 3 mol% Fe2+ but was unable to detect a signal with ESR. Future work will focus on adjusting parameters or reducing noise for ESR or work with a more sensitive instrument.