Interconnected Cobaltocene Complexes on Metal Surfaces

Abstract

Interconnected molecular magnetic centers on metallic surfaces are of interest for molecular spintronics. Complexes composed of two or three cobaltocene units linked by naphthalene or benzene groups are successfully deposited on Au(111) and Cu(111) by sublimation and electrospray deposition. Low-temperature scanning tunneling microscopy and spectroscopy are employed to investigate the deposited compounds and their spin state. Although all molecules are composed of the same magnetic cobaltocene unit, only one compound shows a zero-bias feature compatible with a Kondo resonance, whose amplitude varies from molecule to molecule. The amplitude variation and its absence for the other investigated complexes are attributed to different molecule–substrate coupling, which is strongly influenced by the linker. Parameters influencing the molecule–substrate coupling and molecular properties are extracted from the experimental data. These key parameters should be considered for future strategies of interconnected magn...