C180O2, a V-shaped fullerene trimer

C180O2 is synthesized simply by heating a mixture of C-60 and C60O1-3. Electrospray ionization generates doubly charged anions that are assigned as C120O1-6 and C180O2-6. From C60O2+2C60-->C180O2, we propose a V-shaped structure for C180O2 which retains the bonding sites of the two oxygen atoms in C60O2. Under similar reaction conditions, adducts containing C-70 and C70O building blocks are not observed. Laser desorption ionization mass spectra of C70O indicate that the C-O bond in C70O is weak, providing a plausible account for the difficulty in the formation of C130O and C140O.