The saturation of the excess electron binding energy in AlnF3n+1- (n = 1-5) anions

► The superhalogen AlnF3n+1- (n = 1-5) anions possess VDEs in the 9.8-12.4 eV range. ► The VDE increase for the AlnF3n+1- anions is observed for n raising from 1 to 4. ► The VDE saturation is predicted when the number of central Al atoms achieves 4. ► The largest excess electron detachment energy (12.40 eV) is estimated for Al4F13-.