Si10 and photoabsorption spectra of mid-sized silicon clusters

✍ Scribed by Tapio T. Rantala; Daniel A. Jelski; Thomas F. George

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 458 KB
• Volume: 232
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(94)01342-s

✦ Synopsis

The photoabsorption spectra of various isomers of Sito, Sig, Silt and other silicon clusters are calculated using a tight-binding method. Remarkable similarities between the calculated results and the experimental spectra for mid-sized clusters are noted. It is suggested that the mid-sized clusters are composed of aggregates of smaller clusters.

Recently, Rinnen and Mandich (RM) [1] have presented stunning evidence of great similarities in the photoabsorption spectra of medium-sized clusters Sils-Si41. They report six peaks that recur in the spectra of all species, located at 3. 05, 3.27, 3.63, 3.90, 4.94 and 5.25 eV (peaks labelled (1)-( 6) in what follows), shown in Fig. 1. In addition, there are peaks at about 1.9 eV and 2.5-2.7 eV that occur in the spectra reproduced in their paper. RM offer three possible explanations, the first being a 'common bonding network which persists and extends as the cluster grows in size'. The second possibility implies the existence of what might be called a 'chromophore', i.e. a group of atoms which has approximately the same structure over an entire range of cluster sizes. The third possibility, rejected by RM and, to our knowledge all other authors, is that the clusters exist as van der Waals aggregates of smaller clusters. We present