OPTIMAS researchers are developing molecular switches

For a wide variety of applications in information and sensor technology, it is of interest to manufacture smallest structures of a few nanometers on surfaces in a targeted manner. A cooperation of OPTIMAS teams from physics and chemistry was able to achieve an important research result in the framework of the Transregio Collaborative Research Center SFB / TRR 88 3MET. It was possible to deposit a dinuclear molybdenum complex on a copper surface in a submonolayer film and to investigate its self-assembly process using scanning tunneling microscopy. They found that the complexes on the surface adopt different conformations depending on the temperature, which are reversibly interconvertible. At temperatures below 106 K, an arrangement in complex chains with a width of about 5 nm is found. When the temperature is raised, two-dimensional networks are formed.

The chains differ from the networks in the interaction of the individual complexes with each other and in the interaction with the copper surface. These interactions influence the properties of the Mo atoms in the complex, and thus its physical properties. Results of this study will allow future tailoring of new materials with dimensions of less than 10 nm on the basis of these cooperative effects. If, for example, magnetic complexes were used, information could be switched temperature-dependently and new spintronics and spinterface materials could be developed.

The article has recently been published in the renowned journal Advanced Functional Materials 2017, 1703544

Jobynson Kollamana, Zheng Wei, Lu Lyu, Manuel Zimmer, Fabian Dietrich, Tobias Eul, Johannes Stöckl, Mahalingam Maniraj, Stefano Ponzoni, Mirko Cinchetti, Benjamin Stadtmüller, Markus Gerhards, Martin Aeschlimann
Control of Cooperativity through a Reversible Structural Phase Transition in MoMo-Methyl/Cu(111)
http://onlinelibrary.wiley.com/doi/10.1002/adfm.201703544/full