Density Functional Theory Study of CsC_n⁻ (n = 1−10) Clusters

Abstract

In this paper, we report the design of numerous models of CsC(n)(-) (n = 1-10). By means of B3LYP density functional method, we carried out geometry optimization and calculation on the vibrational frequency. We found that the CsC(n)(-) (n = 4-10) clusters with Cs lightly embraced by C(n) are ground-state isomers. The structures are composed of C(n)(2-) and Cs(+) with the former being electronically stabilized by the latter. When n is even, the C(n) (n = 4-10) chain is polyacetylene-like. The CsC(n)(-) (n = 1-10) with even n are found to be more stable than those with odd n, and the result is in accord with the relative intensities of CsC(n)(-) (n = 1-10) observed in mass spectrometric studies. In this paper, we provide explanations for such trend of even/odd alternation based on concepts of the highest vibrational frequency, incremental binding energy, electron affinity, and dissociation channels.

Analysis and fragmentation of organic samples by (low‐energy) dynamic SIMS

“…Here, they are even much more pronounced. This distribution agrees with both the variation of the binding energy of ground‐state isomers C n Cs − ( n = 1–10) clusters and the electron affinity of C n Cs clusters,14 It has also been calculated that the C n Cs − ( n = 4–10) ground‐state structure is composed of Cs + and C n 2− with Cs slightly embraced by C n − For each impact energy, almost identical distributions of C n Cs − have been obtained for C 60 , Alq 3 and CuPC, however, they change with increasing impact energy. For the lowest impact energy (250 eV), even–odd oscillations are seen up to n = 13.…”