The manipulation of spin states at the molecular scale is of fundamental importance for the
development of molecular spintronic devices. One of the feasible approaches for the
modification of a molecular spin state is through the adsorption of certain specific atoms or
molecules including H, NO, CO, NH 3, and O 2. In this paper, we demonstrate that the local
spin state of an individual iron phthalocyanine (FePc) molecule adsorbed on an Au (111)
surface exhibits controllable switching by hydrogen adsorption, as evidenced by using first …