Robust spin crossover and memristance across a single molecule

A nanoscale molecular switch can be used to store information in a single molecule. Although the switching process can be detected electrically in the form of a change in the molecule′s conductance, adding spin functionality to molecular switches is a key concept for realizing molecular spintronic devices. Here we show that iron-based spin-crossover molecules can be individually and reproducibly switched between a combined high-spin, high-conduction state and a low-spin, low-conduction state, provided the individual molecule is decoupled from a metallic substrate by a thin insulating layer. These results represent a step to achieving combined spin and conduction switching functionality on the level of individual molecules. Switches made up of single molecules form the basis for the concept of molecular electronics. Miyamachi et al. demonstrate that an iron-based spin crossover molecule can be switched between different spin states, provided it is decoupled from a metallic substrate by a thin insulating layer.