| The main content of this paper is the preparation of novel ordered organic supramolecularpowdered and layer-by-layer multilayer thin-filmed metal complexes based on the self-assemblyapproach, and the study of their magnetic behaviors. The aim is quest for the relationship of thestructure of polymer, the kind of metal ions and the magnetic property of the correspondingcomplex. The studies of the magnetic properties of these multilayer films and supramolecularpowders will not only contribute to the research concerning the relationship of structure andmagnetism, but also provide some useful information for the novel functional materials withelectric and magnetic properties.Three kinds of polymers, which containing bithiazole ring, pyridine ring or phenanthrolinering, have been synthesized in this paper. The coordinated supramolecules and correspondingmultilayer films, such as DABT/PAA-M2+, DABT-Ni2+/PAA, (PAA/DABT)20×2-M2+,(DABT/M2+/PAA)15×2, (PSSM/P3MAAP)powde, (PSSM/P4MAAP)powder, (PSSM/P3MAAP)20×2,(PSSM/P4MAAP)20×2, (PSSM/PMPMA)powder and (PSSM/PMPMA)20×2 have been prepared bythe self-assembly method. The multilayer films were obtained on the HDPE substrate, while thesupramolecules were prepared in solutions. The structures of the molecule, polymers,supramolecules and multilayer films were determined by FT-IR,1H NMR,UV-vis,AFM andelemental analysis. The metal contents were measured by complexometric titration andinductively coupled plasma emission spectrometer (ICP).The magnetic properties of these materials were measured by a PPMS-9T magnetometer(QUANTUM DESIGN), which include magnetization versus temperature, magnetization versusapplied field, magnetic susceptibility versus temperature and magnetic hysteresis. Themeasurement results reveal that the system containing bithiazole rings displayed differentmagnetic behaviours not only for the supramolecules but also for the multilayer films, althoughthe component and structure are similar. Most of the supramolecular powders are softferromagnet, except that DABT/PAA-Cu2+ and DABT-Fe2+/PAA exhibit special ferrimagneticproperties. All multilayer films display strong ferromagnetic properties with typical "S" shape of the hysteresis loop. For the system containing copper ions, the relative saturation magnetization(Ms) of the multilayer films (DABT/Cu2+/PAA)15×2 and (PAA/DABT)20×2-Cu2+ is about 2-4times as high as that of the corresponding supramolecular powders, and the value ofCurie-Weiss temperature also increases more than 5 times. The film (DABT/Ni2+/PAA)15×2 showhigh specific magnetization, up to Curie-Weiss temperature (θ=242 K). It is noteworthy that afairly high value of relative saturation magnetization (Ms=37.3 emu.g-1) is observed for the film(PAA/DABT)20×2-Ni2+.In the pyridine system, for the bulk supramolecular powders, (PSSNi/P3MAAP)powder and(PSSCu/P3 MAAP)powder display better ferromagnetic behaviours, while the(PSSCu/P4MAAP)powder is a ferrimagnet. And the temperature of the magnetic order phase forthe powders containing P3MAAP is higher than others, which coule be attributed to the differentcoordinated structure. All films display strong soft ferromagnetic properties, and thecharacteristic temperature, including the temperature of the magnetic order phase, thetemperature of the magnetic saturation phase and the temperature of the magnetic trasition phase,is higher than those of the corresponding supramolecules. It is found that the multilayer film(PSSNi/P4MAAP)20×2 exhibits a fairly high value of relative saturation magnetization (Ms=8.79emu.g-1), while the film (PSSCu/P3MAAP)20×2 shows a high Curie-Weiss temperature (θ=212K).The PSSM/PMPMA multilayer films exhibit a self-improvement behavior with the increasingnumbers of cycles of deposition. The increasingly enhanced magnetic property mainly lies inthree aspects: the relative saturation magnetization, Curie-Weiss temperature and S shapehysteresis loop. It is noteworthy that the relative saturation magnetization (Ms=9.6 emu.g-1) ofthe multilayer film (PSSNi/PMPMA)20×2 was about 30 times as high as that of the film(PSSNi/PMPMA)3×2. The differences observed in the magnetic ordering temperature reflect thespecific structural arrangements of the compounds on the substrate surface. Such behavior ismainly caused by the stronger ferromagnetic interactions among paramagnetic spins in theregular three-dimensional framework than in planar structure.With the increasing number ofassembled bilayer, the multilayer films show different magnetic properties, which changes from diamagnetic property, magnetic switch with a transition temperature to ferromagnetic property.The system containing Ni2+ displays higher relative saturation magnetization and lowerCurie-Weiss temperature, not only for the supramolecules but also for the multilayer films. Forthe twenty bilayers film (PSSCu/PMPMA)20×2 and (PSSNi/PMPMA)20×2, the relative saturationmagnetization and Curie-Weiss temperature are both higher than those of the bulksupramolecular powders (PSSCu/PMPMA)powder and (PSSNi/PMPMA)powder.By comparing the magnetic properties of all the systems, we can also find that the relativesaturation magnetization of the supramolecules and films containing P3MAAP, P4MAAP andPMAMP is discovered at high level, even higher than the previous report, but the value is lowerthan that of the supramolecules and multilayer films containing DABT, coming from the highmolecular weigh of the PSS, P3MAAP, P4MAAP and PMPMA.
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