Overhauser effect difference experiments proved a linear structure for the formed perchlorates of 1‐aza‐9‐azonia‐1H‐benz[f]indene, 1‐aza‐9‐azoniaanthracene, 1,10‐diaza‐4a‐azonia‐9‐thiacyclopenta[b]fluorene, 6‐aza‐7‐azoniabenz[a]anthracene and 6,7‐diaza‐11a‐azoniabenz[a]anthracene derivatives. NOE difference experiments, together with 2D proton‐proton and proton‐carbon correlation measurements, allowed the