Decorating (C60)n+, n = 1-3, with CO2 at low temperatures: Sterically enhanced physisorption

- Physisorption of CO2 to C60 monomer, dimer and trimer cations is observed for the first time in the mass spectra of He nanodroplets sequentially doped with C60 and CO2 and exposed to electron ionization at 50 eV.
- Stability anomalies apparent for (C60)2+(CO2)8 and (C60)3+(CO2)1,2 are consistent with preferential adsorption to the “groove” in the dimer and the two “dimples” in the trimer cations.
- This is illustrated vividly with a computed visualization of the physisorption.