Silicon MEMS cantilevers coated with a 200 nm thin layer of the molecular spin crossover
complex [Fe (H 2 B (pz) 2) 2 (phen)](H 2 B (pz) 2= dihydrobis (pyrazolyl) borate and phen=
1, 10-phenantroline) were actuated using an external magnetic field and their resonance
frequency was tracked by means of integrated piezoresistive detection. The light-induced
spin-state switching of the molecules from the ground low spin to the metastable high spin
state at 10 K led to a well-reproducible shift of the cantilever's resonance frequency (Δf r …