Molecular Based Magnetic Materials and Magnetic Nanoparticles
Α) Single molecule magnetic materials
Molecular based magnetic materials may have significant impact on several emerging quantum technologies like quantum computers, magnetic cooling and high density recording media.
Single molecule magnets are molecules containing paramagnetic ions (transition metals or rare earth ions). Essential these molecules display paramagnetic behavior. Depending of the paramagnetic ion and its molecular environment, some molecules can display slow relaxation phenomena of their magnetic moment.
Single-molecule magnets, behave like a superparamagnet, where below the so called blocking temperature the magnetization freeze on the time scale comparable to the time scale of the measuring probe.
In close collaboration with the groups “Crystallography and Coordination Chemistry of Materials”, “Molecular Magnetic and Bioinorganic Spectroscopy” of our Program “Magnetism and Superconductivity: Advanced Materials and Applications”, and external collaborators we carry out intense research in mononuclear and polynuclear magnetic complexes in an effort to understand the
factors being responsible for the magnetic states and the dynamics of the magnetization. Our contribution concerns the magnetic measurements (ac and dc) and their analysis.
Fig. 1 and Fig. 2 show some representative examples of our results, regarding the magnetic measurements
Fig 1 shows the field dependent magnetization plotsat 2-10 K and the 3D plots of the entropy change in 2-10 K and 0-5 T for [Cu7Gd2(L2)4(HL2)2(piv)4(MeOH)5].
Fig. 2 Field-dependent magnetization plots at 2–10 K and (b) 3D plots of the entropy change in 2–10 K and 0–5 T for Cu7Gd2(L2)4(HL2)2(piv)4)(MeOH)5]∙4.3MeOH0.5H2O(2∙4.3MeOH0.5H2O).
Β) Magnetic nanoparticles for therapeutic applications
One of the most important application of the magnetic oriented nanotechnology is the use of magnetic nanoparticles (NP) as for contrast media and therapeutic agents. Iron based NPs are the most investigated since they can be used for drug delivery, imaging and when magnetically activate employed as local heat sources in cancer hyperthermia. In collaboration with Prof. Eleni Efthimiadou, we have contributed in this field carrying out the magnetic characterization of the magnetic nanoparticles. The figures below show the morphology and the temperature dependence of the magnetic moment of iron nanoparticles used in hyperthermia experiments