In addition, DLPNO-MP2 /def2-TZVP optimizations in the gas phase were conducted for small neutral MAO structures and their anions, while electronic energies of the optimized structures were calculated at RI-MP2 /def2-TZVP level of theory. Frozen-core DLPNO-CCSD(T) /def2-TZVPD single point calculations were also carried out at the corresponding DLPNO-MP2/def2-TZVP optimized geometries. For ion-pairing studies reported in Table , the smaller def2-TZVP basis set was used with the DLPNO-CCSD(T) method. DLPNO-MP2, RI-MP2, and DLPNO-CCSD(T) calculations were carried out using Orca 5.0.3, with tight DLPNO thresholds for energy calculations and default thresholds for geometry optimizations. All other calculations were carried out using Gaussian 16. Quasi-harmonic corrections (qh) to the entropy and enthalpy were employed using the cut-off frequency of 100 cm -1 and corrections to reduced translational entropy (tr) in solution were calculated by the method described by Whitesides and coworkers. All the corrections were employed using the Goodvibes script, modified to include molarities and molecular volumes of fluorobenzene, which were required to calculate free volume.