  We experimentally demonstrated that the AYFFF self-assemblies adsorbed with
various monovalent cations (Na+, K+, and Li+) show unexpectedly super strong
paramagnetism. The key to the super strong paramagnetism lies in the hydrated
cation-{\pi} interactions between the monovalent cations and the aromatic rings
in the AYFFF assemblies, which endows the AYFFF-cations complex with magnetic
moments.
