Investigation of a Tetrathiafulvalene-Based Fe2+ Thermal Spin Crossover Assembled on Gold Surface

A thick film and a monolayer of tetrathiafulvalene-based Fe2+ spin-crossover complex have been deposited by solution on a Au (111) substrate, attempting both self-assembling monolayer protocol and a simpler drop-casting procedure. The thermally induced spin transition has been investigated using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). Temperature-dependent investigations demonstrated the retention of the switching behavior between the two spin states in thick molecular films obtained by drop-casting, while in the monolayer sample, the loss of the spin-crossover properties appears as a possible consequence of the strong interaction between the sulfur atoms of the ligand and the gold substrate.

Automated summary

A thick film and a monolayer of tetrathiafulvalene-based Fe2+ spin-crossover complex were deposited on an Au (111) substrate using a solution. The thermally induced spin transition was studied using XPS and XAS. The results showed that the switching behavior between the two spin states could be retained in thick molecular films obtained by drop-casting, while the monolayer sample lost the spin-crossover properties possibly due to the strong interaction between the sulfur atoms of the ligand and the gold substrate.