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Updated: Nov 16, 2025
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Multinuclear Ag Clusters Sandwiched by Pt Complex Units: Fluxional Behavior and Chiral-at-Cluster Photoluminescence
Shinnosuke Horiuchi1,2, Sangjoon Moon1, Akitaka Ito3
1Division of Chemistry and Materials Science, Graduate School of Engineering, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki, 852-8521, Japan.
Abstract:
Multinuclear Ag clusters sandwiched by Pt complex units were synthesized and characterized by single crystal X-ray diffraction and NMR studies. The sandwich-shaped multinuclear Ag complexes showed two different types of fluxional behavior in solution: rapid slippage of Pt complex units on the Ag3 core and a reversible demetalation-metalation reaction by the treatment with Cl anion and Ag ion, respectively. The Ag2 complex obtained by demetalation reaction from the Ag3 complex displayed U to Z isomerization. These multinuclear Ag complexes showed strong photoluminescence whose properties depended on the existence of Pt→Ag dative bonds. The Ag3 complex, identified to be "chiral-at-cluster", was optically resolved by the formation of a diastereomeric salt with a chiral anion. The enantiomers show circular dichroism (CD) and circularly polarized luminescence (CPL) properties which is unprecedented for compounds based on a chiral sandwich structure. Theoretical calculations allow to understand their structural features and photophysical properties.
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