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Gold nanoclusters exhibiting concomitant photothermy (PT) and photoluminescence (PL) under near‐infrared (NIR) light irradiation are rarely reported, and some fundamental issues remain unresolved for such materials. Herein, we concurrently synthesized two novel rod‐shaped Au nanoclusters, Au52(PET)32 and Au66(PET)38 (PET = 2‐phenylethanethiolate), and precisely revealed that their kernels were 4 × 4 × 6 and 5 × 4 × 6 face‐centered cubic (fcc) structures, respectively, based on the numbers of Au layers in the [100], [010], and [001] directions. Following the structural growth mode from Au52(PET)32 to Au66(PET)38, we predicted six more novel nanoclusters. The concurrent synthesis provides rational comparison of the two nanoclusters on the stability, absorption, emission and photothermy, and reveals the aspect ratio‐related properties. An interesting finding is that the two nanoclusters exhibit concomitant PT and PL under 785 nm light irradiation, and the PT and PL are in balance, which was explained by the qualitative evaluation of the radiative and non‐radiative rates. The ligand effects on PT and PL were also investigated. [ABSTRACT FROM AUTHOR]

Removing or adding kernel atoms of metal nanoclusters (NCs) without leaving a trace is a substantial challenge because the kernel atoms are inside and covered by the outer staples. However, such kernel tuning is very important for improving the properties and acquiring an in‐depth understanding of the kernel‐property correlation. Photoluminescence (PL) is one of the most intriguing characteristics of metal NCs but has not been well understood until now. Inspired by these challenges/questions, we conducted this study and, for the first time, achieved the traceless removal of two kernel atoms in a gold nanocluster by applying a simple thermal treatment and revealed its impact on PL. Further, we demonstrated that the kernel Au‐Au bond length can be an indicator for a comparison of the PL or kernel charge state between nanoclusters with similar kernel structures and sizes. [ABSTRACT FROM AUTHOR]

Kernel atoms of Au nanoclusters are packed layer‐by‐layer along the [001] direction with every full (001) monolayer composed of 8 Au atoms (Au8 unit) in nanoclusters with formula of Au8n+4(TBBT)4n+8 (n is the number of Au8 units; TBBTH=4‐tert‐butylbenzenelthiol). It is unclear whether the kernel atoms can be stacked in a defective‐layer way along the [001] direction during growth of the series of nanoclusters and how the kernel layer number affects properties. Now, a nanocluster is synthesized that is precisely characterized by mass spectrometry and single‐crystal X‐ray crystallography, revealing a layer stacking mode in which a half monolayer composed of 4 atoms (Au4 unit) is stacked on the full monolayer along the [001] direction. The size and the odevity of the kernel layer number influence the properties (polarity, photoluminescence) of gold nanoclusters. The obtained nanocluster extends the previous formula from Au8n+4(TBBT)4n+8 to Au4n+4(TBBT)2n+8 (n is the number of Au4 units). [ABSTRACT FROM AUTHOR]

Structural isomerism allows the correlation between structures and properties to be investigated. Unfortunately, the structural isomers of metal nanoparticles are rare and genuine structural isomerism with distinctly different kernel atom packing (e.g. face‐centered cubic (fcc) vs. non‐fcc) has not been reported until now. Herein we introduce a novel ion‐induction method to synthesize a unique gold nanocluster with a twist mirror symmetry structure. The as‐synthesized nanocluster has the same composition but different kernel atom packing to an existing gold nanocluster Au42(TBBT)26 (TBBT=4‐tert‐butylbenzenethiolate). The fcc‐structured Au42(TBBT)26 nanocluster shows more enhanced photoluminescence than the non‐fcc‐structured Au42(TBBT)26 nanocluster, indicating that the fcc‐structure is more beneficial for emission than the non‐fcc structure. This idea was supported by comparison of the emission intensity of another three pairs of gold nanoclusters with similar compositions and sizes but with different kernel atom packings (fcc vs. non‐fcc). [ABSTRACT FROM AUTHOR]

Abstract: The emergence of thiolated metal nanoclusters provides opportunities to identify significant and unprecedented phenomena because they are at quantum sizes and can be characterized with X‐ray crystallography. Recently silver nanoclusters have received extensive interest owing to their merits, such as low‐cost and rich properties. Herein, a thiolated silver nanocluster [Ag46S7(SPhMe2)24]NO3 (Ag46 for short) with a face‐centered cubic (fcc) structure was successfully synthesized and structurally resolved by X‐ray analysis. Most importantly, interstitial sulfur was found in the lattice void of Ag46 without lattice distortion or expansion, indicating that the classic theory of interstitial metal solid solutions might be not applicable at quantum size. Furthermore, unprecedented chemical bonds and unique structural features (such as asymmetrically coordinated μ4‐S) were found in Ag46 and might be related to the interstitial sulfur, which is supported by natural population analyses. [ABSTRACT FROM AUTHOR]

Au46(m-MBT)26, Au48(m-MBT)26, gold nanoclusters, photoluminescence, traceless removal Keywords: Au46(m-MBT)26; Au48(m-MBT)26; gold nanoclusters; photoluminescence; traceless removal EN Au46(m-MBT)26 Au48(m-MBT)26 gold nanoclusters photoluminescence traceless removal 1 1 1 04/03/21 20210412 NES 210412 B Nanoclusters b The synthesis and characterization of two novel gold nanoclusters is reported by Nan Xia, Zhikun Wu et al. in their Communication on page 8668. [Extracted from the article]

Just like magic cubes or transformers , metal nanoclusters (ultrasmall nanoparticles) can have the same compositions but different structures. This structural isomerism brings an excellent opportunity for structure–property investigations. In their Communication on page 4510 ff., Z. Wu et al. introduce an ion‐induction synthesis method and obtain the second pair of genuine structural isomers of metal nanoclusters in the solid/liquid phase with distinctly different kernel atom packing (fcc vs. non‐fcc), and reveal photoluminescence that is dependent on the kernel atom packing. [ABSTRACT FROM AUTHOR]