Inhomogeneous effect of particle size on core-level and valence-band electrons:: Size-dependent electronic structure of Cu3N nanoparticles

The present study reports a clear evidence and physical significance of an inhomogeneous effect of particle size on electrons originating from various electronic levels of copper nitride nanoparticles. X-ray photoelectron and optical absorption spectroscopy studies reveal that a direct modification of the valence band due to size effects explained by the more appropriate surface bond contraction model results in a strong increase in the binding energy of valence-band electrons as compared to core-level electrons. (c) 2006 American Institute of Physics.