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Comprehensive Summary Poly‐NHC‐based organometallic assemblies 3‐PF6, 3‐SbF6 and 3‐OTf were obtained and verified by NMR spectroscopy, ESI mass spectrometry and single‐crystal X‐ray diffraction analyses. Controllable structural interconversion was observed between the poly‐NHC‐based organometallic assemblies and their self‐aggregated dimers in solution affected by concentration, solvent and metal ion. 1H NMR spectra of assembly 3‐PF6 in CD3CN at different concentrations demonstrated controllable structural interconversion, and 19F NMR spectrum of assembly 3‐PF6 at high concentration further evidenced the presence of the free hexafluorophosphate anion and encapsulated hexafluorophosphate anion for its two sets of signals. In addition, single‐crystal X‐ray diffraction analysis provided clear evidence that in the solid state, two assemblies 3‐PF6 were vertically stuck, forming a self‐aggregated dimer with an encapsulated hexafluorophosphate anion. Investigating the reversible structural interconversion is beneficial for revealing the intrinsic nature on the atom level and paving the way to design the stimuli‐responsive functional system. [ABSTRACT FROM AUTHOR]

A series of [2]catenanes has been prepared from di‐NHC building blocks by utilizing solvophobic effects and/or π⋅⋅⋅π stacking interactions. The dinickel naphthobiscarbene complex syn‐[1] and the kinked biphenyl‐bridged bipyridyl ligand L2 yield the [2]catenane [2‐IL](OTf)4 by self‐assembly. Solvophobic effects are pivotal for the formation of the interlocked species. Substitution of the biphenyl‐linker in L2 for a pyromellitic diimide group gave ligand L3, which yielded in combination with syn‐[1] the [2]catenane [3‐IL](OTf)4. This assembly exhibits enhanced stability in diluted solution, aided by additional π⋅⋅⋅π stacking interactions. The π⋅⋅⋅π stacking was augmented by the introduction of a pyrene bridge between two NHC donors in ligand L4. Di‐NHC precursor H2‐L4(PF6)2 reacts with Ag2O to give the [Ag2L42]2 [2]catenane [4‐IL](PF6)4, which shows strong π⋅⋅⋅π stacking interactions between the pyrene groups. This assembly was readily converted into the [Au2L42]2 gold species [5‐IL](PF6)4, which exhibits exceptional stability based on the strong π⋅⋅⋅π stacking interactions and the enhanced stability of the Au‐CNHC bonds. [ABSTRACT FROM AUTHOR]

Chiral Au nanoclusters have promising application prospects in chiral sensing, asymmetric catalysis, and chiroptics. However, enantiopure superatomic homogold clusters with crystallographic structures emitting bright circularly polarized luminescence (CPL) remain challenging. In this study, we designed chiral N‐heterocyclic carbenes (NHCs), and for the first time enantioselectively synthesized a pair of monovalent cationic superatomic Au13 clusters. This new enantiomeric pair of clusters has a quasi‐C2 symmetric core and exhibited CPL with an unprecedent solution‐state quantum yield (QY) of 61 % among those of the atomically precise Au nanoclusters. DFT calculations provided insights into the circular dichroism behavior, and revealed the origin of CPL from superatomic Au clusters. This work opens a new avenue for developing novel homochiral nanoclusters using chiral NHC ligands and provides fundamental understanding of the origin of the chiroptics of metal clusters. [ABSTRACT FROM AUTHOR]

Dinuclear silver(I) and gold(I) complexes have been prepared from (NHC‐thiophene)‐substituted ethylene (NHC = N‐heterocyclic carbene). Both the 1,2,3,4‐tetrathienylethene (TTE)‐bridged tetrakisazolium salts (H4‐L1(PF6)4 and H4‐L2(PF6)4) and the 2,2′‐(diphenylethene‐1,1‐diyl)dithiophene (DPDT)‐bridged bisimidazolium ligand precursors H4‐L3(PF6)2 have been prepared and are treated with Ag2O to give dinuclear tetracarbene complexes [Ag2L](PF6)2 (L = L1, L2) and [Ag2(L3)2](PF6)2, respectively. The silver(I) complexes undergo a transmetalation reaction with [AuCl(THT)] (THT = tetrahydrothiophene) to furnish gold(I) NHC complexes with retention of the original structures. All complexes have been characterized by multi‐nuclear magnetic resonance (NMR) and high‐resolution electrospray ionization (HR‐ESI) mass spectrometry, and single‐crystal X‐ray diffraction analysis. The thiophene‐containing NHC complexes exhibit aggregation‐induced emission behavior in acetonitrile/water solutions and temperature‐dependent fluorescence properties. [ABSTRACT FROM AUTHOR]

Developing luminescent radicals with tunable emission is a challenging task due to the limitation of alternative skeletons. Herein, a series of carbene‐triphenylamine hybrids were prepared by the direct C2‐arylation of N‐heterocyclic carbenes with 4‐bromo‐N,N‐bis(4‐methoxyphenyl)aniline. These hybrids showed multiple redox‐active properties and could be converted to carbon‐centered luminescent radicals with blue‐to‐cyan emissions (λmax: 436–486 nm) or nitrogen‐centered luminescent radicals with orange emissions (λmax: 590–623 nm) through chemical reduction or oxidation, respectively. The radical species were characterized by electron paramagnetic resonance spectroscopy, ultraviolet‐visible spectroscopy, and single‐crystal X‐ray diffractometry analysis. Notably, the corresponding nitrogen‐centered radicals exhibited good stability in atmospheric air, and their thermal decomposition temperatures were determined to be above 200 °C. In addition, spectral and theoretical calculations indicate that all radicals exhibit anti‐Kasha emissions. [ABSTRACT FROM AUTHOR]