  The results of computer simulation of the dynamics of fullerene C_20 at
different temperatures are presented. It is shown that, although it is
metastable, this isomer is very stable with respect to the transition to a
lower energy configuration and retains its chemical structure under heating to
very high temperatures, T ~ 3000 K. Its decay activation energy is found to be
E_a ~ 7 eV. Possible decay channels are studied, and the height of the minimum
potential barrier to decay is determined to be U = 5.0 eV. The results obtained
make it possible to understand the reasons for the anomalous stability of
fullerene C_20 under normal conditions.
