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Abstract  

Iron in the fullerite lattice binds fullerences in a sandwich type C60FeC60 complexes. At the concentration C60Fe2 it crystallizes in the monoclinic lattice. The structure is thermally unstable, with the energy release of 606 kJ·mol−1 it returns to fee lattice. Two possible sites in the reconstructed fee lattice are discussed, Fe bond to C60 and Fe inside the C60 cage.

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Abstract  

Fullerences C60 with adamantane (C10H16), hexamethylotetramine (HMT, C6H12N4) or 1,4-diazabicyclooctane (DABCO, C6H12N2) crystallize, at the relative concentration C60/guest=2/1, in the pseudotetragonal lattice in which C60 retains almost the same positions as in pure fullerides. The ‘guest’ molecules occupy the octahedral interstitial sites. The mixed crystals which exhibit interesting physical properties are thermally unstable. The decomposition starts at 40–50°C.

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Abstract  

Molecules that may adopt various stable conformations might be applied to store information. The conformational changes could be induced by suitable polarized tip of STM. For the STM experiments two types of fullerene:ferrocene cycloadducts (C60:Fn) were selected where ferrocene fragment is bound to C60 at the 6-6 bond by different heterocyclic pentagon rings. According to semiempirical quantum chemistry calculation one of them may be used to STM observation without any modification, while the second cycloadduct must be exposed to thermal treatment in order to obtain bistable molecule.

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Journal of Thermal Analysis and Calorimetry
Authors: E. Kowalska, P. Byszewski, R. Diduszko, A. Huczko, and J. Mieczkowski

Abstract  

The crystalline solvates containing fullerenes and (di)methylnaphthalenes were investigated by thermal analyses and X-ray diffraction methods. It was found that C60 with (di)methylnaphthalenes forms two types of stable solvates: either at the molar ratio 1:2 decomposing at temperatures close to 100C or at 1:1 molar ratio decomposing in the temperature range 120–214C. Crystalline lattice and thermal stability of the solvates depends on the structure of the solvent molecules. The strong solute-solvent interaction is also manifested by the modification of the C60 absorption spectra in solution. The results are discussed using semiempirical quantum chemistry methods.

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Journal of Thermal Analysis and Calorimetry
Authors: P. Byszewski, E. Kowalska, R. Diduszko, R. Aleksiyko, M. Berkowski, J. Fink-Finowicki, and J. Kapuśniak

Abstract  

The solid solution crystals, La1–xNdxGaO3 and La1–xPrxGaO3 have been studied by differential scanning calorimetry method; the crystals exhibit the first order phase transition, the temperature of the transition linearly increases with the concentration of Pr or Nd. The structure of the crystals has been determined by X-ray diffraction. The correlation between the phase transition temperature and crystalline structure at the temperature of the phase transition in both solid solution families is discussed.

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Journal of Thermal Analysis and Calorimetry
Authors: E. Kowalska, P. Byszewski, M. Popławska, L. Gładczuk, J. Suwalski, R. Diduszko, and J. Radomska

Abstract  

Properties of FeC60 solid samples were investigated by X-ray diffraction, 57Fe Mssbauer spectroscopy and magnetic measurements in order to examine interaction of iron with fullerene. FeC60 samples were prepared by decomposition of adduct based on the fullerene and ferrocene derivative. The samples exhibited superparamagnetic properties originating from an interaction between FeC60 complexes within nanoparticles. Each nanoparticle consisted of hundreds to thousands complexes. The results of experiments are compared with theoretical studies using PM3 method based on the Neglect of Diatomic Differential Overlap approximation.

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