Coherent vibrational dynamics of Au₁₄₄(SR)₆₀ nanoclusters

Abstract

The coherent vibrational dynamics of gold nanoclusters (NCs) provides important information on the coupling between vibrations and electrons as well as their mechanical properties, which is critical for understanding the...

Suppression of kernel vibrations by layer-by-layer ligand engineering boosts photoluminescence efficiency of gold nanoclusters

“…4g-i, serial Au NCs exhibit similar vibration frequency of 59.0 (1.77 THz), 58.7 (1.76 THz), and 57.3 cm −1 (1.72 THz) but a reduction in the variation amplitude. The relatively lowfrequency vibration in serial NCs indicates the oscillations are categorized into acoustic vibration and are better ascribed to the quadrupolar-like vibration mode which is induced by the periodical expansions and contractions of atoms along one direction associated with out-of-phase oscillations in the perpendicular plane 64,65 . Plenty of pioneering works have confirmed that the oscillation frequency of Au NCs still depends on their overall size, but has a more irregular dependence with respect to larger spherical gold NPs due to the discrete structure of Au NCs and their ligands (Table 2) 56,57,[64][65][66][67][68] .…”

Electron Transfer Dynamics from CsPbBr3 Nanocrystals to Au144 Clusters

“…Additionally, high-resolution transmission electron microscopy (HRTEM) images are provided in the inset of Figure a, which reveals an interplanar distance of 0.58 nm corresponding to the (100) lattice plane. Figure b presents a highly monodispersed and spherical morphology of pure Au 144 NCs with 1.8 ± 0.2 nm average sizes . Furthermore, the TEM image of hybrid CsPbBr 3 -Au 144 (Figure S2) indicates that Au 144 NCs are attached with CsPbBr 3 nanocrystals and the morphology of both CsPbBr 3 nanocrystals and Au 144 NCs does not change after the formation of the hybrid structure.…”

“…Figure 1b presents a highly monodispersed and spherical morphology of pure Au 144 NCs with 1.8 ± 0.2 nm average sizes. 47 Furthermore, the TEM image of hybrid CsPbBr…”

“…The Au 144 NCs display absorption bands at 336, 463, 517, and 700 nm due to electronic transition in the NCs, which agrees with the previous report. 33,47 Furthermore, we have performed the steady-state absorption and photoluminescence experiment of both pure CsPbBr 3 nanocrystals and hybrid CsPbBr 3 -Au 144 system. Figure S4c presents the UV−vis absorption spectra of pure CsPbBr 3 nanocrystals and hybrid CsPbBr 3 -Au 144 system, which show additive spectral features that indicate no ground-state interaction occurs between CsPbBr 3 nanocrystals and Au 144 NCs.…”

Coherent Vibrational Dynamics of Au144(SC8H9)60 Nanoclusters

“…The mechanical properties of metal colloids have potential implications for nanomechanical resonators and mass and chemical sensing. − For metal nanoparticles, the acoustic modes are accurately described using classical continuum models that account for displacive lattice motion resulting from coherent phonon excitation. − It has recently been shown that these models accurately extend to include the low-frequency vibrations of ligand-protected nanoclusters with diameters as small as ∼9 Å and up to 4 nm . Still, other researchers have invoked molecular-like wavepacket models to account for low-frequency ∼1 THz vibrations of nanoclusters in the few-nanometer size range. − Therefore, research addressing the coherent vibrational dynamics of structurally well-defined condensed-phase ligand-protected metal nanoclusters in the few-nanometer range is needed to understand the mechanical properties of nanometals.…”