Employing the dynamic crossed-beams technique, absolute cross section for the electron-impact multiply-ionization and fragmentation of mass-selected negatively-charged fullerene ions C^-_m-> C^q+_m-n (m=60, 70, 84; q=1, 2, 3; n=0, 2, 4) have been measured. The electron energy shans from the respective threshold up to 1 keV. A scaling law has been observed for the magnitude of the cross sections that is a function of the fullerene size m and the charge state q of the product ion. The data indicate that different mechanisms account for the detachment of the extra electron from the negatively-charged fullerene and the formation of a positively-charged ion, respectively. Moreover, the multiple-ionization of a fullerene anion is found to be a sequential process. A novel ionization mechanism is proposed which can be expected to be valid for all negatively-charged molecular or cluster ions which are able to shield the attached electron from the incident electron. Suppport by Deutsche Forschungsgemeinschaft (DFG) is gratefully acknosledged. P.S. thanks the Austrian Academy of Sciences for his APART-fellowship.

Подсчитывается количество просмотров абстрактов ("html" на диаграммах) и полных версий статей ("pdf"). Просмотры с одинаковых IP-адресов засчитываются, если происходят с интервалом не менее 2-х часов.

Дата начала обработки статистических данных - 27 января 2016 г.