EVIDENCE OF LINEAR-CHAIN FOR N-GREATER-THAN-OR-EQUAL-TO 10 CARBON NEGATIVE-ION CLUSTERS REVEALED BY MASS SELECTED PHOTODETACHMENT SPECTROSCOPY

Photodetachment spectra of negative carbon clusters are reported in the size range from 5 through 20 atoms. The clusters were prepared in a supersonic beam by laser vaporization and 2nd (2.3 eV) and 3rd (3.5 eV) harmonics of Nd-YAG laser were used for photodetachment. The resultant data indicate that carbon negative cluster ions in the 10-20 range take the forms of both linear chain and cyclic ring under a certain condition.