Abstract
Carbon cluster ions with a double negative charge, and lifetimes of at least 10 μs, have been produced by sputtering graphite, and observed in a double-focusing mass spectrometer. Ions as small as have been detected. The intensities of the doubly charged clusters ( where n=7–28) follow an alternating pattern, with even-n clusters being more intense than neighboring odd-n clusters. In contrast, even-n singly charged clusters are more intense than odd n for n≤9, and less intense for n≥13, where the clusters are believed to be cyclic.
- Received 30 April 1990
DOI:https://doi.org/10.1103/PhysRevLett.65.625
©1990 American Physical Society