The gauge-including magnetically induced current (GIMIC) is another effective method to reveal the induced current of chemical systems under action of external magnetic field . The GIMIC maps on the ring plane of C 18 -(CO) n (n = 6, 4, and 2), which provides a complementary perspective on aromaticity from the ACID isosurface, are displayed in Fig. . It is clear that the significant diatropic/paratropic currents formed inside/outside the ring for each precursor, from which we can draw the same conclusion as that from ACID analysis that the precursor molecules are all considered to be aromatic.