Oxo-centered carboxylate-bridged trinuclear complexes deposited on Au(111) by a mass-selective electrospray

We explored the possibility to deposit Molecular NanoMagnets (metallorganic complexes) by electrospray. To this end, we developed an apparatus for nondestructive in vacuum deposition of fragile molecular complexes, by modifying a commercial Mass Spectrometer equipped with an electrospray ionization source. Starting from solution, this system creates a beam of ionized molecules which is then transferred into an evacuated region where molecules can be mass selected before deposition. To check the system efficiency, we deposited sub monolayers of oxo-centered carboxylate-bridged trinuclear complexes (Cr-3 and Cr2Ni) on the Au(111) surface. By XPS and STM we determined the deposited molecule stoichiometry and the surface coverage. Results show that this type of apparatus works well for the in vacuum deposition of molecular nanomagnets and, thanks to the reduced dimensions, it is portable and adaptable to facilities requiring UHV.