Communications: Tin cluster anions (Sn(n)-, n=18, 20, 23, and 25) comprise dimers of stable subunits.

Institut für Nanotechnologie, Karlsruher Institut für Technologie, Postfach 3640, 76021 Karlsruhe, Germany.
The Journal of Chemical Physics (Impact Factor: 3.16). 06/2010; 132(21):211102. DOI: 10.1063/1.3442411
Source: PubMed

ABSTRACT The gas phase structures of tin cluster anions Sn(n)(-) have been studied by a combination of trapped ion electron diffraction and density functional theory calculations. In the size range of n=18-25 these clusters comprise dimers of stable subunits. In particular Sn(18)(-) and Sn(20)(-) are homodimers of Sn(9) and Sn(10) subunits, respectively. In Sn(23)(-) two Sn(10) units are linked by three additional bridging atoms and Sn(25)(-) is a heterodimer of Sn(10) and Sn(15) subunits. This rather unexpected growth mode is rationalized by the extraordinary stability of the building blocks Sn(9), Sn(10), and Sn(15).

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