Scanning-tunneling-microscopy study of the solid-phase pureSc2C84metallofullerene

The field-ion–scanning-tunneling microscope has been employed to study the ${\mathrm{Sc}}_2$ ${\mathrm{C}}_{84}$ metallofullerenes as individual-molecule adsorbates and as a solid-phase crystalline film on the Si(100)2×1 surface. The results suggest that the Sc atoms are captured inside the ${\mathrm{C}}_{84}$ cage and that a significant amount of charge transfer to the cage takes place. The properties of ${\mathrm{Sc}}_2$ ${\mathrm{C}}_{84}$ in the solid phase are similar to those of the pristine ${\mathrm{C}}_{84}$ fullerene, i.e., the intermolecular bonding is from the van der Waals interaction. However, the intermolecular distance becomes smaller compared to the pristine ${\mathrm{C}}_{84}$.