The electronic structure of 1 2+ could be illustrated by canonical forms 1 2+ a to 1 2+ d (Fig. ). 1 2+ a depicts a form in which both positive charges are purely localized on the central carbon, whereas 1 2+ c represents the opposite extreme where the positive charges reside solely on the terminal CAAC carbon atoms. The unsymmetrical form 1 2+ d illustrates the slightly higher degree of multiple bonding for central C1-N1 than terminal C2-N1. Based on the structural parameters and DFT calculations, it is apparent that the electronic structure of 1 2+ is highly delocalized 2 and resembles cumulenic 1 2+ b which lies between the extremes of 1 2+ a and 1 2+ c.