Bonding environment and electronic structure of Gd metallofullerene and Gd nanowire filled single-wall carbon nanotubes

Being single-walled carbon nanotubes, archetypical 1D systems with peculiar anisotropic electronic properties, it is possible to infer modifications in a controlled manner by filling their inner hollow space. One successful approach was proposed for Gd, which regards filling with metallofullerenes and a successful transformation into different novel metal and a successful transformation into different novel metal nanowires by a versatile nanochemical reaction. In this contribution we report on a combined high resolution photoemission and X-ray absorption study on Gd@C82 peapods and Gd nanowires. From a detailed analysis of the Gd 4d reponse and the valence band in photoemission we are able to elucidate the changes in the bonding environment and charge transfer in these 1D systems. We observe a clear modification of the low energy electronic properties of the SWCNT by the filling with Gd nanowires. Our findings provide important input to understand the interplay between charge transfer and hyridisation in the nanochemical processes in these hybrid systems and to elucidate their electronic transport properties regarding their application potential in nanoelectronic devices. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim