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Silver chalcogenolate clusters (SCCs) and silver cluster‐assembled materials (SCAMs) are an important category of novel luminescent materials, the emission of which can be modulated by variation of the cluster nodes and linker species. Here, the successfully synthesis of two isostructural 2D SCAMs is reported: Ag12bpa and Ag12bpe are formed by using two linkers with different conformational freedom (bpa=1,2‐bis(4‐pyridyl)ethane, bpe=1,2‐bis(4‐pyridyl)ethylene), with dodenuclear silver chalcogenolate clusters as secondary building units (SBUs). Interestingly, nonluminescent Ag12bpa at room temperature could quickly transform into 1D Ag10bpa, with concomitant dissociation of two silver atoms and the remaining ten silver atoms rearranging in the cluster, thus exhibiting an intense yellow phosphorescence after being triggered by acetonitrile (CH3CN). Similarly, stimulating Ag12bpe with CH3CN, by contrast, gave another 2D structure Ag12bpe‐1b with the distorted SBUs and different topology structure, and both of them are merely red‐emissive at low temperature. To note, after exchanging ligands, room‐temperature nonluminescent 2D Ag12bpe‐1b can be transformed into intensely luminescent 1D Ag10bpa. This linker‐flexibility‐dependent structural transformation and cluster‐based SBU controlled luminescence remains scarce. Our work provides new insights into structure–luminescence relationship in clustered metal–organic frameworks and intelligent stimulus‐responsive luminescent materials. What a SCAM! Isostructural silver cluster‐assembled materials (SCAMs) Ag12bpa and Ag12bpe (bpa=1,2‐bis(4‐pyridyl)ethane, bpe=1,2‐bis(4‐pyridyl)ethylene) were synthesized by using bidentate pyridine to give identical length yet different flexibility. Ag12bpa and Ag12bpe differently respond to acetonitrile: 2D Ag12bpa, which is only red‐emissive at low temperature transforms into yellow‐emissive 1D Ag10bpa at room temperature (see figure). [ABSTRACT FROM AUTHOR]

Abstract: Silver chalcogenolate cluster assembled materials (SCAMs) are a category of promising light‐emitting materials the luminescence of which can be modulated by variation of their building blocks (cluster nodes and organic linkers). The transformation of a singly emissive [Ag12(SBut)8(CF3COO)4(bpy)4]n (Ag12bpy, bpy=4,4′‐bipyridine) into a dual‐emissive [(Ag12(SBut)6(CF3COO)6(bpy)3)]n (Ag12bpy‐2) via cluster‐node isomerization, the critical importance of which was highlighted in dictating the photoluminescence properties of SCAMs. Moreover, the newly obtained Ag12bpy‐2 served to construct visual thermochromic Ag12bpy‐2/NH2 by a mixed‐linker synthesis, together with dichromatic core–shell Ag12bpy‐2@Ag12bpy‐NH2‐2 via solvent‐assisted linker exchange. This work provides insight into the significance of metal arrangement on physical properties of nanoclusters. [ABSTRACT FROM AUTHOR]

Self-assembly of metavanadate and organosilver(I) salts leads to a novel dodecahedrane-like [Ag30( tBuS)20]10+ silver(I) thiolate nanocage that tightly wraps an unusual C2 h polyoxovanadate anion. The polyoxovanadate core undergoes transformation to a D3 d configuration upon acidification, and reverts back to its original C2 h structure upon addition of base. Chromism was observed for the silver(I) thiolate cluster during the configurational change of the central polyoxovanadate core; the color of the solution changes reversibly from green to dark yellow. This work represents the first reported example of chromic polyoxometalate-templated silver(I) thiolate shells that respond to external acid-base stimuli. It also represents an important advance in providing crystallographic proof that structural transformations occur in a nanoscale core-shell cluster. [ABSTRACT FROM AUTHOR]

A novel discrete open high-nuclearity nest-like silver thiolate cluster complex, [Ag33S3(S tBu)16(CF3COO)9(NO3)(CH3CN)2](NO3) ( 1), has been isolated with nitrate and S2− anions acting as structure-directing templates. Its similar nest-like structure has been assembled into an extended layer [Ag31S3(S tBu)16(NO3)9] n ( 2) by adjustment of auxiliary ligand. More interestingly, both complexes exhibit temperature-dependent luminescence of high sensitivity with a large fluorescence enhancement (12-fold for 1, 21-fold for 2), which can be easily recognized by the naked-eye (dramatic red-shift Δ=104 nm for 1, larger Δ=113 nm for 2 at 77 K compared to those at 298 K). The correlation between luminescent thermochromism and temperature-dependent variation of the coordination modes of template NO3− anion, Ag⋅⋅⋅S and Ag⋅⋅⋅Ag distances are also elucidated through variable-temperature single-crystal X-ray crystal structure (VT-SCXRD) analyses. [ABSTRACT FROM AUTHOR]

Utilizing aggregation‐induced emission luminogens (AIEgens) as ligands has proven to be an effective strategy for constructing metal–organic frameworks (MOFs) with intense luminescent properties. However, highly luminescent AIEgen‐based MOFs with adjustable emission properties are rarely achieved because of the rigid conformation of AIEgens in the crystalline state. Here, a dual‐node 3D silver chalcogenolate cluster MOF (1) is designed and synthesized, where the AIE ligand shows relatively flexible and rotatable conformations. The conformations of AIE ligands in 1 are switchable by the absorption/desorption of guest molecules. As a result, 1 exhibited not only intense but also guest molecule switched luminescent properties. More importantly, the switching rate is tunable by using different guest molecules. 1 provides a unique visualized prototype to understand the mechanism of guest‐triggered aggregation‐induced emission in MOFs. A dual‐node 3D silver chalcogenolate cluster metal–organic framework is designed and synthesized, which provides a unique visualized prototype to understand the mechanism of guest‐triggered aggregation‐induced emission in metal–organic frameworks. [ABSTRACT FROM AUTHOR]