Semi-empirical models confirm the stability of bridged dimer structure
s assigned in the literature to C-120, C120O and C120O2, Interpreting
all three as additions across formal double bonds of the C-60 monomers
. Analogous structures are proposed and compared for C-60/C-70 dimers
C-130, C130O, C130O2, C-140, C140O and C140O2.