Size dependence of dipolar ineractions in NPs

Size dependent dipolar interactions in iron oxide nanoparticle monolayer and multilayer Langmuir–Blodgett films.

Matthias Pauly ,  Benoit P. Pichon ,  Pierre Panissod ,  Solenne Fleutot ,  Pedro Rodriguez ,  Marc Drillon and Sylvie Begin-Colin

J. Mater. Chem. 22, 6343 (2012)

Magnetization measurements of NP5, NP9 and NP16 dispersed in a polymer matrix: (a) hysteresis loops at 5 K, (b) ZFC/FC curves measured under a permanent field of 75 Oe and (c) imaginary part of the AC susceptibility. Inset: inverse of the
blocking temperature as a function of the measurement time (dots), and fits to the Néel–Brown law (lines).