International audienc

Some metals such as silver are known to become strong reducers on the nanometer scale. Electron energyloss spectroscopy (EELS) shows that modifications of the electronic structure of metal ions also arise in nanoparticles of gadolinium oxide. Indeed, the oxygen K and gadolinium N 4,5 edges present modifications for particles size below 1.5 nm which are the signature of an hybridization of the initially atomiclike Gd 4f states with the valence band and especially the O p states. These modifications evidence that, like in metals, electron delocalization from metal sites also occurs in oxides on the nanometer scale.