“…However, desorption is a typical colloidal aging process which is closely related to nanoparticle clusterization, the latter tightening single nanoparticle units together in more complex agglomerates [1]. Cluster formation in MF samples, induced either by the application of an external magnetic field [2], reducing the MF sample temperature [3], increasing the MF nanoparticle concentration [4] or by changing the characteristics of the nanoparticle surface molecular layer [5][6][7][8][9], has been investigated to some extend though little effort has been devoted to understand the molecular surfacedesorption process that may leads to nanoparticle clusterization. The influence of the surface grafting on the MF properties has been investigated using for instance static magnetic measurements [5], magnetic resonance [6], optical transmission experiments [7], static magnetic birefringence [8], and photoacoustic spectroscopy [9].…”