In situ pressure study of Rb4C60 insulator to metal transition by Compton scattering.

A.A. Sabouri-Dodaran (1) , Ch. Bellin (2) , G. Loupias (2) , Massimiliano Marangolo (3) , S. Rabii (4) , F. Rachdi (5) , Th. Buslaps (6) , M. Mezouar (6)

1 Institute for Studies in Theoretical Physics and Mathematics
2 IMPMC - Institut de minéralogie et de physique des milieux condensés
3 INSP - Institut des Nanosciences de Paris
4 Department of Electrical and Systems Engineering
5 GDPC - Groupe de Dynamique des Phases Condensées
6 ESRF - European Synchrotron Radiation Facility

Compton scattering has been shown to be a powerful tool for studying the ground state electronic density in real materials. Using synchrotron radiation, we have studied pressure effects on Rb4C60 by measuring the Compton profiles below and above the insulator to metal transition at 0.8 GPa. The experimental results are compared with the corresponding calculated results, obtained from new ab initio energy band structure calculations. These results allow us to quantitatively evaluate contributions to the Compton profiles resulting from the contraction of the unit cell as well as from the contraction of the C60 molecule itself. In this paper, we point out an unexpected contraction of the volume of the C60 molecule, leading to a major effect on the electronic density of the Rb4C60 compound.

Mots clés: rubidium compounds; fullerene compounds; metal-insulator transition; Compton effect; ground states; electronic density of states; ab initio calculations; band structure

A.A. Sabouri-Dodaran, Ch. Bellin, G. Loupias, Massimiliano Marangolo, S. Rabii, et al.. In situ pressure study of Rb4C60 insulator to metal transition by Compton scattering.. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2005, 72, pp.085412. ⟨10.1103/PhysRevB.72.085412⟩. ⟨hal-00021494⟩