ELECTRON-IMPACT INDUCED PRODUCTION AND ISOTOPE-RESOLVED IDENTIFICATION OF C-70(6+) AND SEXTUPLY-CHARGED FRAGMENT IONS OF C-70 AND C-60

Using high resolution isotope-resolved mass spectrometry it was possible to prove the existence of sextuply-charged fullerene ions (i.e. the parent ion C-70(6+), the C70 fragment ions C-68(6+), C-64(6+) C-62(6+), and the C60 fragment ions C-58(6+), C-56(6+), C-52(6+) and C-50(6+)) after electron impact ionization of neutral C70 and C60, respectively. The parent ion C-60(6+) cannot be seen isotopically resolved due to interfering coincidences with the C-50(5+), C-40(4+), C-30(3+), C-20(2+) and C-10+ fragment ions.