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Luban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock‐like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom‐precise fcc silver nanoclusters Ag110(SPhF)48(PPh3)12 (Ag110) and Ag14(μ6‐S)(SPhF)12(PPh3)8 (Ag14). It is worth noting that the Ag110 cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile, Ag110 is the largest known fcc‐based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show that Ag110 is a 58‐electron superatom with an electronically closed shell1S21P61D102S21F142P61G18. Ag110⋅Ag14 can rapidly catalyze the reduction of 4‐nitrophenol within 4 minutes. In addition, Ag110 presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi‐spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters. [ABSTRACT FROM AUTHOR]

Developing efficient and robust hydrogen evolution reaction (HER) catalysts for scalable and sustainable hydrogen production through electrochemical water splitting is strategic and challenging. Herein, heterogeneous Mo8O26‐NbNxOy supported on N‐doped graphene (defined as Mo8O26‐NbNxOy/NG) is synthesized by controllable hydrothermal reaction and nitridation process. The O‐exposed Mo8O26 clusters covalently confined on NbNxOy nanodomains provide a distinctive interface configuration and appropriate electronic structure, where fully exposed multiple active sites give excellent HER performance beyond commercial Pt/C catalyst in pH‐universal electrolytes. Theoretical studies reveal that the Mo8O26‐NbNxOy interface with electronic reconstruction affords near‐optimal hydrogen adsorption energy and enhanced initial H2O adsorption. Furthermore, the terminal O atoms in Mo8O26 clusters cooperate with Nb atoms to promote the initial H2O adsorption, and subsequently reduce the H2O dissociation energy, accelerating the entire HER kinetics. [ABSTRACT FROM AUTHOR]

The introduction of chirality into organic–inorganic hybrid perovskites (OIHPs) is expected to achieve excellent photoelectric and nonlinear materials related to circular dichroism. Owing to the existence of asymmetric center and intrinsic chirality in the chiral OIHPs, the different efficiencies of second harmonic generation (SHG) signal occurs when the circularly polarized light (CPL) with different phases passes through the chiral crystal, which is defined as second harmonic generation circular dichroism (SHG‐CD). Here, the SHG‐CD effect is developed in bulk single crystals of chiral one‐dimensional (1D) [(R/S)‐3‐aminopiperidine]PbI4. It is the first time that CPL is distinguished using chirality‐dependent SHG‐CD effect in OIHPs bulk single crystals. Such SHG‐CD technology extends the detection range to near infrared region (NIR). In this way, the anisotropy factor (gSHG‐CD) through SHG‐CD signal is as high as 0.21. [ABSTRACT FROM AUTHOR]

The only feasible access to non‐face‐centered cubic (FCC) copper was by physical vapor deposition under high vacuum. Now, non‐FCC copper is observed in a series of alkynyl‐protected Cu53 nanoclusters (NCs) obtained from solution‐phase synthesis. Determined by single‐crystal X‐ray crystallography, the structures of Cu53(C≡CPhPh)9(dppp)6Cl3(NO3)9 and its two derivatives reveal an ABABC stacking sequence involving 41 Cu atoms. It can be regarded as a mixed FCC and HCP structure, which gives strong evidence that Cu can be arranged in non‐FCC lattice at ambient conditions when proper ligands are provided. Characterization methods including X‐ray absorption fine structure, XPS, ESI‐MS, UV/Vis, Auger spectroscopy, and DFT calculations were carried out. CuII was shown to successively coordinate with introduced ligands and changed to CuI after bonding with phosphine. The following addition of NaBH4 and the aging step further reduced it to the Cu53 NC. [ABSTRACT FROM AUTHOR]

Excellent nonlinear optical materials simultaneously meet the requirements of large SHG response, phase‐matching capability, wide transparency windows, considerable energy band‐gap, good thermal stability and structure stability. Herein, two new promising nonlinear optical (NLO) crystals LiMII(IO3)3 (MII=Zn and Cd) are rationally designed by the aliovalent substitution strategy from the commercialized α‐LiIO3 with the perfect parallel alignment of IO3 groups. Compared with parent α‐LiIO3 and related AI2MIV(IO3)6, the title compounds exhibit more stable covalent 3D structure, and overcome the racemic twinning problem of AI2MIV(IO3)6. More importantly, both compounds inherit NLO‐favorable structure merits of α‐LiIO3 and show larger SHG response (≈14× and ≈12×KDP), shorter absorption edge (294 and 297 nm) with wider energy band‐gap (4.21 and 4.18 eV), good thermal stability (460 and 430 °C), phase‐matching behaviors, wider optical transparency window and good structure stability, achieving an excellent balance of NLO properties. [ABSTRACT FROM AUTHOR]

Chromium(III)-based metal-organic frameworks (Cr-MOFs) are very attractive in a wide range of investigations because of their robustness and high porosity. However, reports on Cr-MOFs are scarce owing to the difficulties in their direct synthesis. Recently developed postsynthetic routes to obtain Cr-MOFs suffered from complicated procedures and a lack of general applicability. Herein, we report a highly efficient and versatile strategy, namely solvent-assisted metal metathesis, to obtain Cr-MOFs from a variety of FeIII-MOFs, including several well-known MOFs and a newly synthesized one, through judicious selection of a coordinating solvent. The versatility of this strategy was demonstrated by producing Cr-MIL-100, Cr-MIL-142A/C, Cr-PCN-333, and Cr-PCN-600 from their FeIII analogues and Cr-SXU-1 from a newly synthesized MOF precursor, Fe-SXU-1, in acetone as the solvent under very mild conditions. We have thus developed a general approach for the preparation of robust Cr-MOFs, which are difficult to synthesize by direct methods. [ABSTRACT FROM AUTHOR]

Robustheit und Porosität machen Chrom(III)‐basierte Metall‐organische Gerüste (Cr‐MOFs) zu verheißungsvollen Materialien, jedoch ist ihre Synthese relativ schwierig. In der Zuschrift auf S. 6578 ff. beschreiben J. H. Wang, X. M. Zhang et al. die Synthese verschiedener Cr‐MOFs aus den entsprechenden Fe‐MOFs durch solvensvermittelten Metallaustausch unter milden Bedindungen. Die effiziente und flexible Methode bietet einen exzellenten Ansatz für die Synthese stabiler MOFs. [ABSTRACT FROM AUTHOR]