Study of electron momentum density of C60 by compton scattering of synchrotron radiation

The author presents an experimental study on the electronic structure of the C60 and its compounds inserted by heavy ions (K, Rb and Cs). This study has been carried out using the compton spectrometry that allows to reach the electronic density in the pulses space and that is sensitive to the delocalized electron of the solid. Measures have been carried out for the C60 and the compounds KNC60, with N=3,4 and 6 at LURE (Orsay, France) and K1C60, Rb1C60, Rb4C60 and Rb2CS60 at ESRF (Grenoble, France). A new approach has been tested to obtain the radial density in the pulses space of C60, from which the C60 kinetic energy has been calculated in its fundamental electronic state. In the case of the compound K6C60 the ab-initio calculation allows the description of the electronic density after the alkaline to the molecule transfer and the electronic density distortion of this molecule, in face of alkaline ions. For the compounds A3C60 and A4C60 a good agreement between the experimental and theoretical electronic densities has been obtained. On the other hand a disagreement has been pointed for the compound A1C60, between the experimental and the theoretical distortion profile width. (A.L.B.)