X-ray　photoelectron　spectra　(XPS),　near-edge　X-ray　absorption　fine　structure　spectra　(NEXAFS),　and　X-ray　emission　spectroscopy　(XES),　as　well　as　the　ground-state　electronic/geometrical　structures　about　the　significant　classical　isolated-pentagon　rule　(IPR)　isomer　D3h-#24109C78,　the　non-IPR　isomers　C2-#22010C78　and　C1-#23863C78,　and　the　nonclassical　isomer　C2-C78(NC2)　with　its　chlorinated　derivative　C2-C78(NC2)Cl24,　which　are　newly　obtained　in　the　experiment,　have　been　calculated　at　the　density　functional　theory　(DFT)　level.　Significant　differences　have　been　observed　in　the　electronic　structure　and　the　X-ray　spectra.　All　X-ray　spectra　have　shown　strong　isomer　dependence;　consequently,　the　＇fingerprint＇　in　X-ray　spectra　shows　a　very　effective　way　to　isolate　the　fullerene　isomers　above.　As　a　result,　this　work　indicates　that　X-ray　spectroscopy　can　provide　valuable　identification　for　classical　and　nonclassical　fullerenes　as　well　as　their　derivatives　on　experimental　and　theoretical　studies.　©　2019　American　Chemical　Society.