CHAPTER 20: New Nanoscaled Paramagnetic Complexes (NPCs) Based on Porphyrins/Phthalocyanines for Environmental Chemistry

Our work will survey new porphyrin/phthalocyanine complexes with a big magnetocaloric effect (MCE) as environmentally friendly materials in advanced room-temperature magnetic cooling and hyperthermia for analysis as early cancer diagnostics and MRT contrast agents, and for magnetic cell separation. The magnetocaloric effect during the magnetization and heat capacity of functionalized (5,10,15,20-tetraphenylporphyrinato) manganese(iii) ((X)MnTPP), (5,10,15,20-tetraphenylporphyrinato) lanthanide(iii) ((X)LnTPP), (tetraazaporphyrinato) manganese(iii) ((X)MnTAP), (phthalocyaninato) lanthanide(iii) acetate ((AcO)LnPc) and one-electron oxidized (phthalocyaninato) lanthanide(iii) double-decker (LnPc₂˙) complexes in their aqueous suspensions at temperatures of 270–350 K and magnetic induction of 0–1 T were obtained by the microcalorimetric method. The regularities of the influence of a central atom, axial ligand and a macrocycle composition in porphyrin/phthalocyanine complexes on their magnetothermal properties were established. It was shown that coordination of a paramagnetic metal cation with aromatic porphyrin/phthalocyanine having a changeable system of electrons opens prospects to derive magnetic materials with improved magnetic properties, in particular with a large magnetocaloric effect. The MCE values at close to room temperature and magnetic induction of 1 T are 0.35–1.45 and 0.047–0.85 K, respectively in lanthanide(iii) and manganese(iii) complexes based on porphyrins/phthalocyanines.