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Metallo‐supramolecular cages have garnered tremendous attention for their diverse yet molecular‐level precision structures. However, the physical properties of these supramolecular ensembles, which are of potential significance in molecular electronics, remain largely unexplored. We herein constructed a series of octahedral metallo‐cages and cage‐fullerene complexes with notably enhanced structural stability. As such, we could systematically evaluate the electrical conductivity of these ensembles at both the single‐molecule level and aggregated bulk state (as well‐defined films). Our findings reveal that counteranions and fullerene guests play a pivotal role in determining the electrical conductivity of the aggregated state, while such effects are less significant for single‐molecule conductance. Both the counteranions and fullerenes effectively tune the electronic structures and packing density of metallo‐supramolecular assemblies, and facilitate efficient charge transfer between the cage hosts and fullerenes, resulting in a notable one order of magnitude increase in the electrical conductivity of the aggregated state. [ABSTRACT FROM AUTHOR]

Molecular electronics is generally considered an alternative approach for the future fabrication of electronic devices. In the past few decades, benefiting from the impressive advancement in synthetic chemistry there emerged abundant molecular structures that are able to serve as conductive backbones for the electrons to transport through, as well as derivatives containing versatile substituents. Controlling the charge transport through a molecule lays the foundation for incorporating the molecule as a functional component in an active electronic device. In recent years the study on substituent-dependent conductance behavior attracted intensive research interest as it provides a feasible strategy to tune the electron transport in the molecule. In this review, we summarized the influence of substituents on single-molecule conductance and the mechanism of the influence into three aspects: the quantum interference effect, the electronic effect of substituents inducing changes in the energy levels of molecular orbitals, and the conformational restriction of the conductive backbone by the weak interaction between the substituents. [ABSTRACT FROM AUTHOR]

Magnetocaloric effect (MCE) and thermal conductivity of two gadolinium hydroxides, Gd(OH)3 (1) and Gd2O(OH)4(H2O)2 (2), are investigated. Magnetic studies indicate that both 1 and 2 exhibit antiferromagnetic interaction, and the MCE values for 1 and 2 at 2 K and ΔH = 7 T are 62.00 J kg−1 K−1 and 59.09 J kg−1 K−1, respectively. Investigation of their thermal conductivity reveals that the thermal conductivity for 1 is significantly better than that for 2. [ABSTRACT FROM AUTHOR]

Magnetocaloric effect (MCE) and thermal conductivity of two gadolinium hydroxides, Gd(OH)3 (1) and Gd2O(OH)4(H2O)2 (2), are investigated. Magnetic studies indicate that both 1 and 2 exhibit antiferromagnetic interaction, and the MCE values for 1 and 2 at 2 K and ΔH = 7 T are 62.00 J kg−1 K−1 and 59.09 J kg−1 K−1, respectively. Investigation of their thermal conductivity reveals that the thermal conductivity for 1 is significantly better than that for 2. [ABSTRACT FROM AUTHOR]

Three heterometallic cluster complexes {Ln12Mo4} featuring an Ln12 core of a distorted truncated tetrahedron were synthesized with the assistance of four MoO42− anions as ancillary ligands. Magnetic studies of the {Gd12Mo4} cluster revealed a large magnetocaloric effect due to the presence of the large number of weakly coupled Gd(iii) ions. [ABSTRACT FROM AUTHOR]

Metallo-supramolecular cages have garnered tremendous attention for their diverse yet molecular-level precision structures. However, the physical properties of these supramolecular ensembles, which are of potential significance in molecular electronics, remain largely unexplored. We herein constructed a series of octahedral metallo-cages and cage-fullerene complexes with notably enhanced structural stability. As such, we could systematically evaluate the electrical conductivity of these ensembles at both the single-molecule level and aggregated bulk state (as well-defined films). Our findings reveal that counteranions and fullerene guests play a pivotal role in determining the electrical conductivity of the aggregated state, while such effects are less significant for single-molecule conductance. Both the counteranions and fullerenes effectively tune the electronic structures and packing density of metallo-supramolecular assemblies, and facilitate efficient charge transfer between the cage hosts and fullerenes, resulting in a notable one order of magnitude increase in the electrical conductivity of the aggregated state., (© 2024 Wiley-VCH GmbH.)

The Fano resonance in single-molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule-electrode coupling. We demonstrated the room-temperature observation of Fano resonance from electrochemical gated single-molecule conductance and current-voltage measurements of a para-carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single-molecule junctions opens pathways for designs of interference-based electronic devices., (© 2022 Wiley-VCH GmbH.)

1,2-Bis[[(diphenylphosphino)methyl](phenyl)phosphino]ethane (dpmppe) was prepared as a new tetraphosphine, and the corresponding rac and meso stereoisomers were successfully separated in view of their solubility difference in acetone. The substitution of PPh 3 into Pt(PPh 3 ) 2 (C≡CR) 2 (R = aryl) with rac- or meso-dpmppe gives Pt(rac-dpmppe)(C≡CR) 2 or Pt(meso-dpmppe)(C≡CR) 2 , respectively. Using Pt(rac-dpmppe)(C≡CR) 2 or Pt(meso-dpmppe)(C≡CR) 2 as a precursor, PtAg 2 heterotrinuclear cluster complexes were synthesized and characterized by X-ray crystallography. Depending on the conformations of tetraphosphine, the structures of PtAg 2 complexes supported with rac- and meso-dpmppe are quite different. The higher molecular rigidity of rac-dpmppe-supported PtAg 2 complexes results in stronger phosphorescent emission than that of PtAg 2 species with meso-dpmppe. The high phosphorescent quantum yields (as high as 90.5%) in doping films warrant these PtAg 2 complexes as excellent phosphorescent dopants in organic light-emitting diodes (OLEDs). The peak current and external quantum efficiencies in solution-processed OLEDs are 61.0 cd A -1 and 18.1%, respectively. Electroluminescence was elaborately modulated by modifying the substituent in aromatic acetylide and the conformations in tetraphosphine so as to achieve cyan, green, green-yellow, yellow, and orange-red emission.