Alkynyl-Stabilized Superatomic Silver Clusters Showing Circularly Polarized Luminescence

Abstract

We report a new enantiomeric pair of superatomic silver clusters, R/S-Ag 17 , prepared from chiral alkynyl ligands. R-Ag 17 and S-Ag 17 possess C 3 symmetry and emit near-infrared (NIR) light with a quantum yield (QY) of 8.0% under ambient condition as well as NIR circularly polarized luminescence (CPL) as a result of the chirality of the excited states. Both experiments and theoretical calculations indicate for the first time that the CPL originates from transitions between superatomic 1P z (along the C 3 axis) and 1S orbitals. This work opens a new avenue for CPL-active metal nanoclusters by utilizing chiral alkynyl ligands and enlightens the chirality transfer from chiral protecting ligands to superatomic states in metal clusters.

Homoleptic Alkynyl‐Protected Ag15 Nanocluster with Atomic Precision: Structural Analysis and Electrocatalytic Performance toward CO2 Reduction

“…To determine the counterion, Ag 15 NC was characterized by infrared spectroscopy (IR) (Figure S1) and X-ray photoelectron spectroscopy (XPS) (Figure S2). No F1 sp eak with abinding energy of 688 eV was detected, hence,CF 3 COO À is ruled out;but the O1speak at the binding energy of 532 eV [31] can be observed, plus no characteristic vibrational absorption peak of carbonyl group in the IR spectrum, so the counterion of Ag 15 NC is probably CH 3 O À .A san ote,i nt he structure analysis of Ag 15 crystal, the electron cloud density around the counterion is quite low,s ot he counter ions could not be resolved by X-ray single crystal diffraction. Figure 1cpresents the simulated absorbance spectrum of [Ag 15 (CCÀCH 3 ) 12 ] + along with the experimental one.T osimplify the calculation, all C C-t Bu ligands are replaced with C C À CH 3 ,w hich has been regarded as ac ommon choice in the simulation of organic ligand-protected clusters.…”

Frontiers in circularly polarized luminescence: molecular design, self-assembly, nanomaterials, and applications

“…Compared with CPL-active single-valence coinage metal clusters, mixed-valence metal clusters that contain both M(0) and M(I) centers have much room for development due to the novel functions and high-performance properties. In 2021, CPL-active superatomic coinage metal cluster was presented by Zang et al [230]. They prepared and structurally characterized an enantiomeric pair of superatomic silver clusters with symmetric CPL activities by using designed chiral al- kynyl ligands (Figure 20a).…”

Master key to coinage metal nanoclusters treasure chest: 38-metal clusters

“…Nanoclusters (1–3 nm) are a bridge between discrete atoms and plasma nanoparticles. 1–11 This intermediate transition state gives nanoclusters fascinating physicochemical properties, such as optics, 12–15 electrochemistry, 16–18 chirality, 19–27 and catalysis. 28–30 Therefore, it has received extensive attention from chemistry researchers and has become one of the hot topics of research in recent years.…”