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Comprehensive Summary: Metal clusters with photoswitching ligands can undergo magnetic changes under light radiation, which makes them potential optical‐response magnetic‐switching materials. Herein, a photoswitchable Mn‐oxo cluster [MnII15MnIII4(L)18(OH)12(N3)6] (ClO4)2 (C6H5CN)8, (Mn19azo, HL=1‐(hydroxymethyl)‐3,5‐dimethyl‐4‐(phenyldiazenyl)‐pyrazole) has been designed and synthesized to realize the photoswitching behavior. Mn19azo shows quick trans‐to‐cis transformation upon 365 nm light irradiation in CH2Cl2 solution and solid state as confirmed by UV‐Vis spectra. After the powder sample was irradiated for 80 min, the Curie constant of Mn19azo increases by about 7%. The change of magnetic properties can be considered as the result of the change of intermolecular interactions. [ABSTRACT FROM AUTHOR]

Two diphosphine-protected superatom gold selenido nanoclusters, [Au8Se2(dppm)4]2+(SD/Au8a, dppm = Ph2PCH2PPh2) and [Au8Se2(dppe)4]2+(SD/Au8b, dppe = Ph2P(CH2)2PPh2), were obtained by the reduction of [Au(SMe2)Cl] in the presence of Ph3PSe as the selenium ion releasing agents. Both can be regarded as "superatoms" with 1S2 configuration based on the spherical Jellium model. Despite the same metal-ligand binding motifs on the surface and the intrinsic C2 molecular symmetry, the configurations of Au8Se2 kernels in them are different in terms of Au-Au bonded metallic frameworks. SD/Au8a displays a heart-shaped [core + exo] type structure (Au4 tetrahedron core + two exo Au2Se units), whereas the two exo Au2Se counterparts in SD/Au8b are additionally locked by an obvious Au-Au bond, forming a distorted hexagonal Au6 ring with two capping AuSe units appended above and below it. Consequently, they showed different photophysical properties as reflected by their electronic absorption and emission spectra. Especially, both SD/Au8a and SD/Au8b exhibit blue-shifted thermochromic luminescence upon cooling from 293 to 83 K but the latter exhibits anomalous emission intensity evolution trends due to the occurrence of temperature-induced phase transition as revealed by varied-temperature crystallographic analyses. This work not only clearly illustrates the significance of ligands on tuning the kernel structure but also provides two rarely comparable examples for better understanding of the structure-property relationship of gold nanoclusters. [ABSTRACT FROM AUTHOR]

Imine-bridged TTF-π-pyridine derivatives, 2NTTF, 3NTTF and 4NTTF, were synthesized and the cation-binding study was performed. It is noted that with the addition of the micromolar concentration of Pb2+ to the solution, these compounds display remarkable changes in solution color, 1H NMR spectra and electrochemical properties. The nitrogen atom of the imine-bridge in 2NTTF not only serves as a π-conjugated spacer but also participates in the sensing and coordinating properties. [ABSTRACT FROM AUTHOR]

Nitrogen-rich quantum dots (N-dots) were serendipitously synthesized in methanol or aqueous solution at a reaction temperature as low as 50 °C. These N-dots have a small size (less than 10 nm) and contain a high percentage of the element nitrogen, and are thus a new member of quantum-dot family. These N-dots show unique and distinct photoluminescence properties with an increasing percentage of nitrogen compared to the neighboring carbon dots. The photoluminescence behavior was adjusted from blue to green simply through variation of the reaction temperature. Furthermore, the detailed mechanism of N-dot formation was also proposed with the trapped intermediate. These N-dots have also shown promising applications as fluorescent ink and biocompatible staining in C. elegans., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)