Eur. Phys. J. D (2012) 66: 293
https://doi.org/10.1140/epjd/e2012-30467-7

Regular Article

Polarizabilities of Si_N (N = 8–75) clusters from molecular beam electric deflection experiments

Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Petersenstraße 20, 64287 Darmstadt, Germany

^a e-mail: goetz@cluster.pc.chemie.tu-darmstadt.de

Received: 25 July 2012
Received in final form: 25 September 2012
Published online: 27 November 2012

Abstract

We have studied the polarizabilities of neutral silicon clusters with 8 to 75 atoms at 300 K employing the molecular beam deflection technique. In the range of 8 to 30 atoms the polarizability is strongly size-dependent, whereas for clusters up to 75 atoms polarizability approaches the bulk value of 3.71 Å³, estimated from the Clausius-Mossotti relation for α-Si. This indicates a transition in the growing pattern of silicon clusters in this range. For some clusters, i.e. Si₁₈, we observe a significantly increased polarizability compared to the bulk value, which can be interpreted by taking a permanent dipole moment via a simple Langevin-Debye model into account.