Structural Evolution of Anionic Silicon Clusters Si N (20 ≤ N ≤ 45)

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Molecules, spectroscopy, kinetics, environment, & general theory, 2006-01, Vol.110 (3), p.908-912
• Main Authors: Bai, Jaeil, Cui, Li-Feng, Wang, Jinlan, Yoo, Soohaeng, Li, Xi, Jellinek, Julius, Koehler, Christof, Frauenheim, Thomas, Wang, Lai-Sheng, Zeng, Xiao Cheng
• Format: Article
• Language: English
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp055874s

Results of a combined photoelectron spectroscopy and first-principles density-functional study of Si N - clusters in the size range 20 ≤ N ≤ 45 are reported and discussed. Evidence for a prolate-to-near-spherical shape transition at N = 27 is presented. It is shown that the tricapped-trigonal-prism (TTP) structural motif Si9 found in most low-lying clusters Si N -, 9 ≤ N ≤ 19, is replaced or augmented by a series of structural motifs consisting of a bulklike “adamantane” fragment plus a magic-number cluster (Si6, Si7, Si10) or TTP Si9 in low-lying prolate clusters Si N -, N ≥ 20. For 28 ≤ N ≤ 45, almost all low-lying near-spherical clusters Si N - adopt “stuffed-cage”-like structures where the cages are homologous to carbon fullerenes in the sense that they are composed of only five- and six-membered rings. However the arrangement of the “stuffing” atoms is not yet diamondlike.