Fig. 1: Summary of the investigated solvents, cations and anions.

Top: Structural formulae of the strategically substituted and dipole-maximized polar fluorobenzenes xFB with x = 1–5. Bottom left: Ball and Stick models of the Ag+ and NO+ cations. Bottom right: The WCAs [pf]− (= [Al(ORF)4]−) and [al-f-al]− (= [(FRO)3Al-F-Al(ORF)3]−; RF = C(CF3)3) in a representation with the electrostatic potential plotted on an isodensity surface (0.025 e− B−3) using like cut-off values and calculated at the (RI-)BP86/def2-TZVPP level of theory. The scale bar right indicates areas of more negative (red), neutral (green) and positive (blue) surface potentials.