General Assembly of Twisted Trigonal-Prismatic Nonanuclear Silver(I) Clusters

Area of Science:

• Inorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Silver-sulfur clusters are of interest due to their unique structural and electronic properties.
• The synthesis of complex silver clusters often requires careful control of reaction conditions and ligands.

Purpose of the Study:

• To synthesize and characterize a new class of C3-symmetric Ag9 clusters with a twisted trigonal-prism geometry.
• To investigate the luminescent properties and potential applications of these silver clusters.

Main Methods:

• Solvothermal synthesis using polymeric {(HNEt3 )2 [Ag10 (tBuC6 H4 S)12 ]}n, 1,6-bis(diphenylphosphino)hexane (dpph), and various silver salts.
• Single-crystal X-ray diffraction for structural characterization.
• Photoluminescence spectroscopy and cyclic voltammetry for property analysis.

Main Results:

• Four new Ag9 clusters ([Ag9 S(tBuC6 H4 S)6 (dpph)3 (CF3 SO3 )] (1), [Ag9 (tBuC6 H4 S)6 (dpph)3 (CF3 SO3 )2 ]⋅CF3 SO3 (2), [Ag9 (tBuC6 H4 S)6 (dpph)3 (NO3 )2 ] ⋅NO3 (3), and [Ag9 (tBuC6 H4 S)7 (dpph)3 (Mo2 O7 )0.5 ]2 ⋅2 CF3 COO (4)) were synthesized.
• Cluster 1 exhibits yellow luminescence at room temperature, with intensity increasing and shifting to shorter wavelengths upon cooling.
• The luminescent properties of cluster 1 suggest its potential as a molecular luminescent thermometer.

Conclusions:

• The synergetic effect of mixed ligands plays a crucial role in constructing Ag9 twisted trigonal prisms.
• Cluster 1's temperature-dependent luminescence makes it a promising candidate for thermometry applications.
• The study provides insights into the structure-property relationships of silver-sulfur clusters.