The
synthesis and isolation of an ambient stable perylenediimide radical
anion is reported, and its precursor is established as one of the
strongest electron acceptors. The radical anion shows absorption up
to 1400 nm and is stable in mixed aqueous solution. Interestingly,
the radical anion can organize two electron-deficient molecules over
its surface to form a π-stacked array. Calculations revealed
weak spin polarization via noncovalent interactions. Such interactions
are of significance for magnetic exchange and catalysis.