Preparation and Spectroscopic Properties of Monolayer-Protected Silver Nanoclusters

Ag nanoclusters protected by 2-phenylethanethiol (1), 4-fluorothiophenol (2), and l-glutathione (3) ligands were successfully synthesized. The optical properties of the prepd. Ag nanoclusters were studied. The absorption signal of Ag@SCH2CH2Ph in toluene can be found at 469 nm, and Ag@SPhF in THF shows 2 absorption bands at 395 and 462 nm. Ag@SG in H2O absorbs at 478 nm. Mie theory in combination with the Drude model clearly indicates the peaks in the spectra originate from plasmonic transitions. The damping const. as well as the dielec. const. of the surrounding medium was detd. The CD spectra of Ag nanoclusters protected by the 3 ligands (1-3) were also studied. As expected, only the clusters of type 3 gave rise to chiroptical activity across the visible and near-UV regions. The location and strength of the optical activity suggest an electronic structure of the metal that is highly sensitive to the chiral environment imposed by the glutathione ligand. The morphol. and size of the prepd. nanoclusters were analyzed by using TEM. TEM anal. showed that the particles of all 3 types of Ag clusters were small than 5 nm, with an av. size of ∼2 nm. The anal. of the FTIR spectra elucidated the structural properties of the ligands binding to the nanoclusters. By comparing the IR absorption spectra of pure ligands with those of the protected Ag nanoclusters, the disappearance of the S-H vibrational band (2535-2564 cm-1) in the protected Ag nanoclusters confirmed the anchoring of ligands to the cluster surface through the S atom. By elemental anal. and TGA, the Ag/S ratio and, hence, the no. of ligands surrounding a Ag atom could be detd. [on SciFinder(R)]     «

Ag nanoclusters protected by 2-phenylethanethiol (1), 4-fluorothiophenol (2), and l-glutathione (3) ligands were successfully synthesized. The optical properties of the prepd. Ag nanoclusters were studied. The absorption signal of Ag@SCH2CH2Ph in toluene can be found at 469 nm, and Ag@SPhF in THF shows 2 absorption bands at 395 and 462 nm. Ag@SG in H2O absorbs at 478 nm. Mie theory in combination with the Drude model clearly indicates the peaks in the spectra originate from plasmonic transitions...     »

Aging Plasmon (in spectroscopic properties of monolayer-protected silver nanoclusters) IR spectra (mid-IR prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) Clusters Nanoparticles (nanoclusters prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) Particle size (nanoscale prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) Adsorbed monolayers Chemisorbed substances Circular dichroism Particle size distribution Thermogravimetric analysis UV and visible spectra (prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) silver nanocluster fluorothiophenol glutathione phenylethanethiol optical spectra CD thermogravimetry UV visible spectra silver nanocluster fluorothiophenol glutathione phenylethanethiol IR spectra silver nanocluster fluorothiophenol glutathione phenylethanethiol     «

Aging Plasmon (in spectroscopic properties of monolayer-protected silver nanoclusters) IR spectra (mid-IR prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) Clusters Nanoparticles (nanoclusters prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) Particle size (nanoscale prepn. and spectroscopic properties of monolayer-protected silver nanoclusters) Adsorbed monolayers Chemisorbed substances Circular dichroism Particle size distribution The...     »

CAN 156:462838 Optical, Electron, and Mass Spectroscopy and Other Related Properties 70-18-8 (γ-L-Glutamyl-L-cysteinylglycine); 371-42-6 (4-Fluorothiophenol); 4410-99-5 (2-Phenylethanethiol); 7761-88-8 (Silver nitrate) Role: RCT (Reactant), RACT (Reactant or reagent) (in prepn. and spectroscopic properties of monolayer-protected silver nanoclusters); 16940-66-2 (Sodium borohydride) Role: RGT (Reagent), RACT (Reactant or reagent) (in prepn. and spectroscopic properties of monolayer-protected silver nanoclusters); 70-18-8DP (L-Glutathione); 371-42-6DP (4-Fluorothiophenol); 4410-99-5DP (2-Phenylethanethiol); 7440-22-4DP (Silver) Role: PEP (Physical, engineering or chemical process), PRP (Properties), SPN (Synthetic preparation), PREP (Preparation), PROC (Process) (prepn. and spectroscopic properties of monolayer-protected silver nanoclusters)     «

CAN 156:462838 Optical, Electron, and Mass Spectroscopy and Other Related Properties 70-18-8 (γ-L-Glutamyl-L-cysteinylglycine); 371-42-6 (4-Fluorothiophenol); 4410-99-5 (2-Phenylethanethiol); 7761-88-8 (Silver nitrate) Role: RCT (Reactant), RACT (Reactant or reagent) (in prepn. and spectroscopic properties of monolayer-protected silver nanoclusters); 16940-66-2 (Sodium borohydride) Role: RGT (Reagent), RACT (Reactant or reagent) (in prepn. and spectroscopic properties of monolayer-protected...     »