Structure, bonding and reactions within protonated acetone-methanol cluster ions

We have studied the structure and reactivity of the acetone-methanol cluster series {(C₃H₆O)_m(CH₃OH) _n}H⁺ as a function of cluster size. Conventional mass spectra are mainly dominated by the three series of protonated acetone-methanol cluster ions, (C₃H₆O)_m=1-3(CH ₃OH)_nH⁺. In the CID spectra of the (C ₃H₆O)₁(CH₃OH)_nH ⁺ series, we observed two different reaction channels: the loss of CH₃OH and the loss of C₃H₆O. The former dominates regardless of the cluster size. For the (C₃H ₆O)₂(CH₃OH)_nH⁺ series, the CID result reveals a change in the preferred reaction pathway as a function of cluster size. For the (C₃H₆O)₃(CH ₃OH)_nH⁺ series, the loss of C₃H ₆O dominates.