C180O2, a V-shaped fullerene trimer

C180O2 is synthesized simply by heating a mixture of C60 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 C70 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.