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In this work, we present NMR and electron spin resonance (ESR) data on KBaCsC60 fulleride. The obtained 13C MAS NMR (MAS: magic angle spinning) spectrum shows two resonances, an intense and sharp line at 188ppm and a weak and small peak at 180ppm. We attribute the first one to the KBaCsC60, which is the dominant phase, and the last one to residual AC60 (A=K or Cs) phase present in the sample. The ESR results reveal a metallic behaviour of the studied compound, in contrast to the insulating A4C60 (A=K, Rb, Cs) fullerides. [Copyright &y& Elsevier]

Abstract: The equation of state (EOS) of Rb4C60 is determined by high-pressure X-ray diffraction measurements. We observe an abrupt jump in the compressibility of Rb4C60 between 0.5 and 0.8GPa which is attributed to a structural phase transition preserving the tetragonal symmetry. Pressure effects on electronic density are studied by measuring Compton profiles below and above the transition. The ab initio calculation of the electronic structure is used to obtain theoretical equation of state, which agrees well with the experimental results. The calculations are used to quantitatively identify different contributions to the Compton profiles. In particular, we point out an unexpected contraction of the C60 molecular volume under pressure which brings about significant effects on the electronic density of Rb4C60 compound. [Copyright &y& Elsevier]