  In spite of the high potential of endohedral metallofullerenes (EMFs) for
application in biology, medicine and molecular electronics and recent efforts
in EMF synthesis, the variety of EMFs accessible by conventional synthetic
methods remains limited and does not include, for example, EMFs of late
transition metals. We propose a method in which EMF formation is initiated by
electron irradiation in aberration-corrected high-resolution transmission
electron spectroscopy (AC-HRTEM) of a metal cluster surrounded by amorphous
carbon inside a carbon nanotube serving as a nano-reactor and apply this method
for synthesis of nickel EMFs. The use of ACHRTEM makes it possible not only to
synthesize new, previously unattainable nanoobjects but also to study in situ
the mechanism of structural transformations. Molecular dynamics simulations
using the state-of-the-art approach for modeling the effect of electron
irradiation are performed to rationalise the experimental observations and to
link the observed processes with conditions of bulk EMF synthesis.
