Bottom-up construction of chiral metal-peptide assemblies from metal cluster motifs.

The exploration of artificial metal-peptide assemblies (MPAs) is one of the most exciting fields because of their great potential for simulating the dynamics and functionality of natural proteins. However, unfavorable enthalpy changes make forming discrete complexes with large and adaptable cavities from flexible peptide ligands challenging. Here, we present a strategy integrating metal-cluster building blocks and peptides to create chiral metal-peptide assemblies and get a family of enantiopure [R-/S-NiL] (n = 2, 3, 6) MPAs, including the R-/S-NiL capsule, the S-NiL trigonal prism, and the R-/S-NiL octahedron cage.

Enhancing the performance of molecule-based piezoelectric sensors by optimizing their microstructures.

By combining the rigidity of inorganic components with the flexibility of organic components, molecule-based ferroelectrics emerge as promising candidates for flexible, self-powered piezoelectric sensors. While it is well known that the performance of piezoelectric sensor devices depends not only on the materials' piezoelectric properties but also on the device architecture, research into enhancing molecule-based piezoelectric sensor performance through microstructure optimization has never been investigated. Here, we report the synthesis of a molecule-based ferroelectric, [(2-bromoethyl) trimethylammonium][GaBr] ([(CH)NCHCHBr][GaBr]) (1), which exhibits a piezoelectric coefficient ( ) of up to 331 pC N.

Ln/Cu Bimetallic Nanoclusters with Enhanced NIR-II Luminescence.

Coinage-metal clusters with excellent luminescence properties have attracted considerable interest due to their intriguing structures and potential applications. However, achieving strong near-infrared (NIR) luminescence in these clusters is highly challenging. Here, we have successfully synthesized the first Ln/Cu bimetallic clusters, formulated as [LnCuOCl(2-MeO-PhC≡C)] (ClO) (Ln = Yb for , Er for , and Gd for ).

Achievement of a giant electromechanical conversion coefficient in a molecule-based ferroelectric.

Molecule-based ferroelectrics are promising candidates for flexible self-powered power supplies (, piezoelectric generators (PEGs)). Although the large electromechanical conversion coefficients ( × ) of piezoelectrics are key to enhancing the performance of PEGs in their nonresonant states, it remains a great challenge to obtain molecule-based piezoelectrics with large × . Here, we report a molecule-based ferroelectric [(CH)NCHCHCl][GaBr] (1) that exhibits the largest piezoelectric coefficient (∼454 pC N) and electromechanical conversion coefficient (4953.

Strong NIR-II Magneto-Optical Activity of a Chiral SmCu Cage.

The magneto-optical response of chiral materials holds significant potential for applications in physics, chemistry, and biology. However, exploration of the near-infrared (NIR) magneto-optical response remains limited. Herein, we report the synthesis and strong NIR-II magneto-optical activity of three pairs of chiral 34 clusters of (Ln = Sm, Gd, and Dy).

High-Nuclearity LnAl Clusters: Neonates of Open Hollow Dodecahedral Cage Families.

Open hollow dodecahedral cage clusters have long been a coveted target in synthetic chemistry, yet their creation poses immense challenges. Here we report two open hollow dodecahedral lanthanide-aluminum (Ln-Al) heterometallic cage clusters, namely, [LnAl(μ-OH)(μ-OH)(OAc)(HO)](ClO)·(MeCN)·(HO), (Ln = Dy and = 27, = 300 for ; Ln = Y and = 28, = 420 for ). Remarkably, the 350 metal atoms in and display a Keplerate-type four-shell structure of truncated icosidodecahedron@dodecahedron@dodecahedron@icosidodecahedron.

Achieving Magnetic Refrigerants with Large Magnetic Entropy Changes and Low Magnetic Ordering Temperatures.

Adiabatic demagnetization refrigeration (ADR) is a promising cooling technology with high efficiency and exceptional stability in achieving ultralow temperatures, playing an indispensable role at the forefront of fundamental and applied science. However, a significant challenge for ADR is that existing magnetic refrigerants struggle to concurrently achieve low magnetic ordering temperatures () and substantial magnetic entropy changes (-Δ) at ultralow temperatures. In this work, we propose the combination of Gd and Yb to effectively regulate both -Δ and in ultralow temperatures.

pH-Driven Rotational Configuration of Keggin-Fe Clusters and Their Transformations.

Keggin-Fe clusters are considered foundational building blocks or prenucleation precursors of ferrihydrite. Understanding the factors that influence the rotational configuration of these clusters, and their transformations in water, is vital for comprehending the formation mechanism of ferrihydrite. Here, we report syntheses and crystal structures of four lanthanide-iron-oxo clusters, namely, [DyFe(Gly)(μ-OH)(μ-OH)(μ-O)(HO)]·13ClO·19HO (), [DyFe(Gly)(μ-OH)(μ-O)(HO)]·13ClO·14HO (), [PrFe(Gly)(μ-OH)(μ-O)(μ-O)(HO)]·6ClO·20HO (), and [PrFe(Gly)(μ-OH)(μ-O)(HO)]·13ClO·22HO (, Gly = glycine).

Ln Induced Thermally Activated Delayed Fluorescence of Chiral Heterometallic Clusters LnAg.

A series of TADF-active compounds: 0D chiral Ln-Ag(I) clusters L-/D-LnAg-0D (Ln=Eu/Gd) and 2D chiral Ln-Ag(I) cluster-based frameworks L-/D-LnAg-2D (Ln=Gd) has been synthesized. Atomic-level structural analysis showed that the chiral Ag(I) cluster units {AgS} in L-/D-LnAg-0D and L-/D-LnAg-2D exhibited similar configurations, linked by varying numbers of [Ln(HO)] (x=6 for 0D, x=3 for 2D) to form the final target compounds. Temperature-dependent emission spectra and decay lifetimes measurement demonstrated the presence of TADF in L-LnAg-0D (Ln=Eu/Gd) and L-GdAg-2D.

Accurate Prediction of the Magnetic Ordering Temperature of Ultralow-Temperature Magnetic Refrigerants.

Adiabatic demagnetization refrigeration is known to be the only cryogenic refrigeration technology that can achieve ultralow temperatures (≪1 K) at gravity-free conditions. The key indexes to evaluate the performance of magnetic refrigerants are their magnetic entropy changes (-Δ) and magnetic ordering temperature (). Although, based on the factors affecting the -Δ of magnetic refrigerants, one has been able to judge if a magnetic refrigerant has a large -Δ, how to accurately predict their remains a huge challenge due to the fact that the of magnetic refrigerants is related to not only magnetic exchange but also single-ion anisotropy and magnetic dipole interaction.

Enhancement of Magneto-Chiral Dichroism Intensity by Chemical Design: The Key Role of Magnetic-Dipole Allowed Transitions.

Here we report on the strong magneto-chiral dichroism (MChD) detected through visible and near-infrared light absorption up to 5.0 T on {ErNi} metal clusters obtained by reaction of enantiopure chiral ligands and Ni and Er precursors. Single-crystal diffraction analysis reveals that these compounds are 34 heterometallic clusters, showing helical chirality.

Magneto-optical Properties of Chiral CoLn and CoLn (Ln = Dy and Er) Clusters.

A series of chiral heterometallic Ln-Co clusters, denoted as and (Ln = Dy and Er), were synthesized by reacting the chiral chelating ligand (/)-2-(1-hydroxyethyl)pyridine (Hmpm), CoAc·4HO, and Ln(NO)·6HO. and exhibit perfect mirror images in circular dichroism within the 320-700 nm range. Notably, the and clusters display pronounced magnetic circular dichroism (MCD) responses of the hypersensitive f-f transitions I-G at 375 nm and I-H at 520 nm of Er ions.

Tuning Electrocatalytic Water Oxidation Activity: Insights from the Active-Site Distance in LnCu Clusters.

Atomically precise metal clusters serve as a unique model for unraveling the intricate mechanism of the catalytic reaction and exploring the complex relationship between structure and activity. Herein, three series of water-soluble heterometallic clusters LnCu, abbreviated as LnCu-AC (Ln = La, Nd, Gd, Er, Yb; HAC = acetic acid), LnCu-IM (Ln = La and Nd; IM = Imidazole), and LnCu-IDA (Ln = Nd; HIDA = Iminodiacetic acid) are presented, each featuring a uniform metallic core stabilized by distinct protected ligands. Crystal structure analysis reveals a triangular prism topology formed by six Cu ions around one Ln ion in LnCu, with variations in Cu···Cu distances attributed to different ligands.

Single-molecule magnet behavior in heterometallic decanuclear [LnFe] (Ln = Y, Dy, Ho, Tb, Gd) coordination clusters.

Five decanuclear lanthanide-iron clusters, formulated as [LnFe(hmp)(μ-OH)(μ-OH)(μ-O)(HO)]·6ClO·HO ( ≈ 8, Ln = Y for 1; ≈ 6, Ln = Dy for 2; ≈ 6, Ln = Ho for 3; ≈ 7, Ln = Tb for 4; ≈ 7, Ln = Gd for 5, Hhmp = 2-(hydroxymethyl)pyridine), have been synthesized and structurally characterized. Single-crystal structural analysis reveals that the cluster consists of six face-sharing defective cubane units. Dynamic magnetic investigations indicated that cluster 2 exhibits single-molecule magnet behavior under a zero dc field eliciting an effective energy barrier of = 17.

Soluble GdCu clusters: effective molecular electrocatalysts for water oxidation.

The water oxidation half reaction in water splitting for hydrogen production is extremely rate-limiting. This study reports the synthesis of two heterometallic clusters (GdCu-IM and GdCu-AC) for application as efficient water oxidation catalysts. Interestingly, the maximum turnover frequency of GdCu-IM in an NaAc solution of a weak acid (pH 6) was 319 s.

A Doped Lanthanide-Based Coordination Polymer Exhibiting High Relative Sensitivity to Ratiometric Luminescent Thermometers at 440 K.

Ratiometric luminescent thermometers with excellent performance often require the luminescent materials to possess high thermal stability and relative sensitivity (). However, such luminescent materials are very rare, especially in physiological (298-323 K) and high-temperature (>373 K) regions. Here we report the synthesis and luminescent property of [TbEu(pfbz)(phen)Cl] (), which not only exhibits high in physiological temperature but also has a up to 7.

Exploration and Insights on Topology Adjustment of Giant Heterometallic Cages Featuring Inorganic Skeletons Assisted by Machine Learning.

Inorganic molecular cages are emerging multifunctional molecular-based platforms with the unique merits of rigid skeletons and inherited properties from constituent metal ions. However, the sensitive coordination bonds and vast synthetic space have limited their systematic exploration. Herein, two giant cage-like clusters featuring the organic ligand-directed inorganic skeletons of Ni[LaNi(IDA)(OH)(CO)(HO)]·(NO)·(HO) (, 5 × 5 × 3 - CO) and [LaNi(IDA)(OH)(CO)(NO)(HO)]·(NO)·(HO) (, 5 × 5 × 5 - CO) were discovered by a high-throughput synthetic search.

Uranyl Polyoxotungstate Cluster for Visible-Light-Driven Heterogeneous C-H Selective Fluorination.

The selective fluorination of C-H bonds at room temperature using heterogeneous visible-light catalysts is both interesting and challenging. Herein, we present the heterogeneous sandwich-type structure uranyl-polyoxotungstate cluster Na{Na@[(SbWO)(UO)(POOH)]}·46HO (denoted as ) to regulate the selective fluorination of the C-H bond under visible light and room temperature. This is the first report in which uranyl participates in the fluorination reaction in the form of an insoluble substance.

From Helices to Crystals: Multiscale Representation of Chirality in Double-Helix Structures.

Single crystals with chiral shapes aroused the interest of chemists due to their fascinating polarization rotation properties. Although the formation of large-scale spiral structures is considered to be a potential factor in chiral crystals, the precise mechanism behind their formation remains elusive. Herein, we present a rare phenomenon involving the multitransfer and expression of chirality at micro-, meso-, and macroscopic levels, starting from chiral carbon atoms and extending to the double-helical secondary structure, ultimately resulting in the chiral geometry of crystals.

Conductive Lanthanide Metal-Organic Frameworks with Exceptionally High Stability.

Electrically conductive metal-organic frameworks (MOFs) have been extensively studied for their potential uses in energy-related technologies and sensors. However, achieving that goal requires MOFs to be highly stable and maintain their conductivity under practical operating conditions with varying solution environments and temperatures. Herein, we have designed and synthesized a new series of {[Ln(μ-O)(μ-OH)(INA)(GA)](CFSO)(HO)} (denoted as , Ln = Gd, Tm, and Lu, INA = isonicotinic acid, GA = glycolic acid) single crystals, where electrons are found to transport along the π-π stacked aromatic carbon rings in the crystals.

Magnetoelectric effect generated through electron transfer from organic radical to metal ion.

Magnetoelectric (ME) materials induced by electron transfer are extremely rare. Electron transfer in these materials invariably occurs between the metal ions. In contrast, ME properties induced by electron transfer from an organic radical to a metal ion have never been observed.

Circularly polarized luminescence and performance modulation of chiral europium-titanium (EuTi)-oxo clusters.

The designed synthesis of chiral luminescent molecules with excellent circularly polarized luminescence (CPL) performance and high quantum yield (QY) levels has attracted great interest but remains very challenging. Herein, we report three pairs of chiral europium-titanium-oxo clusters featuring both modest CPL characteristics and high QY levels (up to 79%), which can be regulated by switching between different ligand substituents.

Water-driven Successive Structural Transformation in a Two-Dimensional (2D) Lead-Free Hybrid Double Perovskite.

Hybrid organic-inorganic halide perovskites (HOIPs) have received continued interest for their structure diversity and potential application in optoelectronic, solar cells, nonlinear optics (NLO), and ferroelectrics. Structural symmetry breaking induced by water molecules in single-crystal-to-single-crystal (SCSC) transformations is beneficial to develop ferroelectrics or second-harmonic generation (SHG) materials. Along this line, a water-containing two-dimensional (2D) double perovskite, (CHN)AgBiBr·HO (), was prepared.

Thermally induced charge transfer in a quinoid-bridged linear Cu compound.

Charge transfer always occurs in molecular valence tautomers, leading to the redistribution of electron density and exhibiting electrical, optical, and magnetic properties, and can be further controlled by multiple external stimuli such as temperature, light and electric field. The design of molecule-based materials capable of charge transfer remains a challenge. Herein, a linear Cu compound [(CH)NCHCHBr][CuL(HO)] (HL = chloranilic acid) (1) with a multi-center donor-acceptor architecture was constructed using the redox-active chloranilic acid quinoid ligand.