AbstractThe He(Iα) photoelectron (PE) spectra of tris(perfluorocyclobuta)benzene4(F)3,3,4,4,7,7,8,8,11,11,12,12‐Dodecafluorotetracyclo[8.2.0.02,5.06,9]dodeca‐1,5,9‐triene, tris(perfluorocyclopenta)benzene5(F)1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9‐Octadecafluoro‐2,3,4,5,6,7,8,9‐octahydro‐1H‐trindene., tetrakis(perfluorocyclobuta)cyclooctatetraene6(F)3,3,4,4,7,7,8,8,11,1l,l2,l2,l5,15,16,16‐Hexadecafluoropentacyclo[12.2.0.02,5.06,9.010,13]hexadeca‐1,5,9,13‐tetraene., and of tetrakis(perfluorocyclopenta)cyclooctatetraene7(F)1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12‐Tetracosafluoro‐1,2,3,4,5,6,7,8,9,10,11,12‐dodeca‐hydrotetracyclopenta[a,c,e,g]cyclooctene.are reported. A tentative assignment of the PE spectra is derived by empirical correlation with those of relevant reference compounds. The results suggest that6(F) retains theD4h‐conformation in the gas phase,i.e. A conformation with a planar cyclooctatetraene ring, as observed in the crystal. All four compounds exhibit a sharp increase of their first ionization energies, relative to the corresponding parent hydrocarb