Self-assembled monolayer of Cr7Ni molecular nanomagnets by sublimation.

We show, by complementary spectroscopic and STM analysis, that Cr7Ni derivativesare suitable to be sublimed in UHV conditions. Cr7Ni-bu weakly bonds to gold surface and can diffuserelatively freely on it, forming monolayers with hexagonal 2D packing. Conversely, by adding afunctional thiol group to the central dibutylamine, a covalent bond between the molecule andsurface gold adatoms is promoted, leading to a strong molecular grafting and the formation of adisordered monolayer. These two examples demonstrate the possibility to control the assembly of alarge molecular complex, as rationalized by DFT calculations that establish different energy scales inthe deposition processes. Moreover, low-temperature XMCD sprectra show that the magneticfeatures of Cr7Ni rings deposited in UHV on gold remain unchanged with respect to those of thecorresponding bulk sample.