Organic-coated iron-chromium oxide (chromite) nanoparticles have been prepared by using the thermal decomposition procedure. For this purpose, the substratebimetallic acetatewas treated with oleic acid and dodecylamine as co-ligands in trichloroacetic acid solvent at high temperature (320 C). The main characteristics and behaviors of the obtained nanoparticles were investigated by combined techniques.The size of the obtained nanoparticles was around 11 nm, as estimated by TEM, WAXD and SAXS, which were in good agreement. The bimetallic nature of the nanoparticles was emphasized by X-ray energy dispersive spectrometry (EDX) and their structure was confirmed by WAXD. The Fourier transform infrared (FTIR) spectrum revealed the bands characteristic to metal oxides as well as to the organic components and confirmed the replacement of the acetate with long chain ligands. The co-existence of the organic coatings and metallic core induced a special behavior that was studied by thermogravimetric analysis, differential scanning calorimetry and polarized optical microscopy. The coated bimetallic nanoparticles proved to be thermostable up to 252 C and thermotropic showing a highly organized crystalline smectic mesophase (3D plastic mesophase). The organic part alone, in the absence of the inorganic component, did not develop this self-assembly. The results of the magnetic measurements suggest superparamagnetic behavior of the iron-chromium oxide nanoparticles and a weak ferromagnetic behavior.

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Antiferromagnetic order at TN = 23 K has been identified in Mn(III)F(salen), salen = H14C16N2O2, an S = 2 linear-chain system. Using single crystals, specific heat studies performed in magnetic fields up to 9 T revealed the presence of a field-independent cusp at the same temperature where 1 H NMR studies conducted at 42 MHz observed dramatic changes in the spin-lattice relaxation time, T1, and in the linewidths. Neutron powder diffraction performed on a randomlyoriented, as-grown, deuterated (12 of 14 H replaced by d) sample of 2.2 g at 10 K and 100 K did not resolve the magnetic ordering, while low-field (less than 0.1 T) magnetic susceptibility studies of single crystals and randomly-arranged microcrystalline samples reveal subtle features associated with the transition. Ensemble these data suggest a magnetic signature previously detected at 3.8 T for temperatures below nominally 500 mK is a spin-flop field of small net moments arising from alternating subsets of three Mn spins along the chains.

The theoretical and experimental study of low-temperature heat capacity of InSe intercalated by nickel as a function of temperature has been carried out in range 0.3-30 K. The effect of intercalation by nickel on phonon heat capacity (C ph ) of InSe has been investigated. Two peaks observed in relative change of phonon specific heat (∆C ph /C ph ) suggested non-Debye excess in heat capacity for all intercalated Ni