Saturation magnetization of ferromagnetic and ferrimagnetic nanocrystals at room temperature

The size-dependent saturation magnetization M s ( D ) of ferromagnetic and ferrimagnetic nanocrystals at room temperature, without free parameters, has been predicted in terms of a size-dependent cohesive energy model, where D denotes the diameter of nanoparticles or the thickness of thin films. The given M s ( D ) functions, which are also a function of interface conditions for substrate supported nanocrystals, drop as D decreases, which correspond to the available experimental and theoretical results for ferromagnetic Ni films, Fe, Co, Ni nanoparticles, and ferrimagnetic γ-Fe 2 O 3 , Fe 3 O 4 , MnFe 2 O 4 and CoFe 2 O 4 nanoparticles.