Symmetry breaking in ligand-protected gold clusters probed by nonlinear optics.
The first hyperpolarizabilities of [Au25(SR)18](-1/0) and Au38(SR)24 clusters were determined by Hyper-Rayleigh Scattering. A strong dependence on the molecular symmetry was observed, and we explore two strategies to destroy the center of inversion in [Au25(SR)18](-1/0), protection by chiral ligands and alloying of the cluster with silver. This may open new avenues to applications of Au : SR clusters in second-order nonlinear optics.
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium. thierry.verbiest@fys.kuleuven.be stefan.knoppe@chem.kuleuven.be.
Nick
N
Van Steerteghem
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium. thierry.verbiest@fys.kuleuven.be stefan.knoppe@chem.kuleuven.be.
Stijn
S
Van Cleuvenbergen
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium. thierry.verbiest@fys.kuleuven.be stefan.knoppe@chem.kuleuven.be.
Steven
S
Deckers
Department of Chemistry and Biochemistry, 352 Coulter Hall and University of Mississippi, 38677 Oxford, MS, USA.
Chanaka
C
Kumara
Department of Chemistry and Biochemistry, 352 Coulter Hall and University of Mississippi, 38677 Oxford, MS, USA.
Amala
A
Dass
Department of Chemistry and Department of Physics, Nanoscience Center, University of Jyväskylä, 40014 Jyväskylä, Finland.
Hannu
H
Häkkinen
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium. thierry.verbiest@fys.kuleuven.be stefan.knoppe@chem.kuleuven.be.
Koen
K
Clays
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium. thierry.verbiest@fys.kuleuven.be stefan.knoppe@chem.kuleuven.be.
Thierry
T
Verbiest
Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium. thierry.verbiest@fys.kuleuven.be stefan.knoppe@chem.kuleuven.be.
Stefan
S
Knoppe