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Photogenerated radicals are an indispensable member of the state‐of‐the‐art photochromic material family, as they can effectively modulate the photoluminescence and photothermal conversion performance of radical‐induced photochromic complexes. Herein, two novel radical‐induced photochromic metal–organic frameworks (MOFs), [Ag(TEPE)](AC) ⋅ 7/4H2O ⋅ 5/4EtOH (1) and [Ag(TEPE)](NC) ⋅ 3H2O ⋅ EtOH (2), are reported. Distinctly different topological networks can be obtained by judiciously introducing alternative π‐conjugated anionic guests, including a new topological structure (named as sfm) first reported in this work, describing as 4,4,4,4‐c net. EPR data and UV–Vis spectra prove the radical‐induced photochromic mechanism. Dynamic photochromism exhibits tunability in a wide CIE color space, with a linear segment from yellow to red for 1, while a curved coordinate line for 2, resulting in colorful emission from blue to orange. Moreover, photogenerated TEPE* radicals effectively activate the near‐infrared (NIR) photothermal conversion effect of MOFs. Under 1 W cm−2 808 nm laser irradiation, the surface temperatures of photoproducts 1* and 2* can reach ~160 °C and ~120 °C, respectively, with competitive NIR photothermal conversion efficiencies η=51.8 % (1*) and 36.2 % (2*). This work develops a feasible electrostatic compensation strategy to accurately introduce photoactive anionic guests into MOFs to construct multifunctional radical‐induced photothermal conversion materials with tunable photoluminescence behavior. [ABSTRACT FROM AUTHOR]

Upon dehydration, a dinuclear Fe(ii)–Dy(iii) cluster {FeDy(H2O)2} undergoes two-step single-crystal-to-single-crystal (SCSC) transformation, giving another dinuclear cluster {FeDy(H2O)} and finally a tetranuclear cluster {Fe2Dy2}. Further, both the single crystals of {FeDy(H2O)} and {Fe2Dy2} can return to {FeDy(H2O)2} by rehydration. This multistep SCSC transformation leads to notable OFF/Part/ON switching of single-molecule magnet behaviour. [ABSTRACT FROM AUTHOR]

A wheel-shaped Dy(iii) single-molecule magnet (SMM), supported by polyoxotungstates, Cs15K8Na12[K⊂{(AsW9O33)Dy(H2O)2}6]·71H2O (1), is described here. The polyanion of 1 possesses an idealized S6 symmetry. The effective energy barrier (68 K) obtained from magnetic studies is consistent with the deconvolution of the luminescence spectra of 1. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of metal nitrates and ligand bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)methane (H2L1) gave three cluster compounds, {Cr2}, {Zn12} and {Fe8}. Notably, methylene group of H2L1 was in situ oxidized either to hydroxymethylated (L2-O)3− in the metallo-ring {Zn12} or to a rigid carbonylated (L3=O)2− in the screw-type {Fe8}. In light of comparative experimental results, NO3− was deduced to be of a catalytic role in the ligand oxidation. Metal ion could be regarded as an 'induced' tool for clusters generation in self-assembly process. [ABSTRACT FROM AUTHOR]

The pentagonal bipyramidal single-ion magnets (SIMs) are among the most attractive prototypes of high-performance single-molecule magnets (SMMs). Here, a fluorescence-active phosphine oxide ligand CyPh2PO (=cyclohexyl(diphenyl)phosphine oxide) was introduced into [Dy(CyPh2PO)2(H2O)5]Br3⋅2 (CyPh2PO)⋅EtOH⋅3 H2O, and combined dynamic magnetic measurement, optical characterization, ab initio calculation, and magneto-optical correlation of this high-performance pseudo- D5 h DyIII SIM with large Ueff (508(2) K) and high magnetic hysteresis temperature (19 K) were performed. This work provides a deeper insight into the rational design of promising molecular magnets. [ABSTRACT FROM AUTHOR]

Two Ln(iii) (Ln = Ce or Nd) complexes based on [15-MC-6] (MC = metallacrown) and phosphine oxide are reported for the first time with the Ln(iii) ion featuring nearly perfect hexagonal bipyramidal LnO8 geometry, with pseudo-D6h symmetry. Magnetic measurements reveal that both behave as single-ion magnets (SIMs), where the slow relaxation is dominated by the Raman mechanism. [ABSTRACT FROM AUTHOR]

We have reported two unprecedented single-ion magnets (SIMs) with the homoatomic LnN10 coordination geometry, where the central Ln (Ln = DyIII or ErIII) ion is interlocked by two pentadentate ligands (N5) affording a low symmetry polyhedron. Studies of dynamic magnetic behaviours show an effective energy of 79(4) K for [Dy(N5)2]3+ and 59(4) K for [Er(N5)2]3+, respectively. [ABSTRACT FROM AUTHOR]

The use of paramagnetic molecules as cryogenic coolants usually requires relatively large fields to obtain a practical cooling effect. Thus, research into magnetic molecular materials with larger MCEs in fields of ≤2 T is the main focus in this area. In this work, the crystal structure, magnetic susceptibility and isothermal magnetization for the inorganic framework material GdF3 were measured, and the isothermal entropy change was evaluated up to 9 T. Thanks to the combination of the large isotropic spin of Gd3+, the dense structure and weak ferromagnetic interaction, an extremely large −ΔSm for GdF3 was observed up to 528 mJ cm−3 K−1 for Δμ0H = 9 T, proving it to be an exceptional cryogenic magnetic coolant. [ABSTRACT FROM AUTHOR]

The first example of phototunable SMMs has been reported. Upon UV irradiation, variations of the coordination sphere around Dy(iii) ions actually affect the magnetic behaviour of the compound via [2+2] cycloaddition reaction, leading to a magnetic transformation from the SMM behaviour to a field-induced slow relaxation. [ABSTRACT FROM AUTHOR]

The first “half-sandwich” YbIII single-ion magnets (SIMs) based on [12-MCZn(ii)-4] are reported, in which the central ytterbium ion is coordinated by YbO8 geometry in D4d symmetry. The anisotropic barrier is extracted from the analysis of static, dynamic magnetism and emission spectrum offering an insight into the magneto-optical correlation. [ABSTRACT FROM AUTHOR]

The perturbation to the ligand field around the lanthanide ion may significantly contribute to the magnetic dynamics of single molecule magnets. This can be demonstrated by two typical Dy4 cluster-based single molecular magnets (SMMs), [Dy4X2(μ3-OH)2(μ-OH)2(2,2-bpt)4(H2O)4]X2·2H2O·4EtOH (X = Cl and Br for 1 and 2, respectively), which were constructed by using 3,5-bis(pyridin-2-yl)-1,2,4-triazole (2,2-bptH) as the polynuclear-chelating ligand. Alternating-current (ac) magnetic susceptibility measurements show that the energy barriers in complexes 1 and 2 were immensely enhanced by comparing with our previous work due to the optimization of the ligand field around DyIII ions. Remarkably, their high thermal active barriers at 190 K (1) and 197 K (2) under a zero applied external dc magnetic field are also among the highest within the reported tetranuclear lanthanide-based SMMs. [ABSTRACT FROM AUTHOR]

Enantiopure chiral cubic cages have been diastereoselectively synthesized for the first time. Chiral amines lead to the isolation of O symmetric homochiral cubic cages, while an achiral amine gives a racemic mixture. CD enhancement is observed as a result of configuration rigidity. [ABSTRACT FROM AUTHOR]

A novel multifunctional complex [Dy4(OH)2(bpt)4(NO3)6(EtOH)2]·EtOH (1, Hbpt = 3,5-bis(pyridin-2-yl)-1,2,4-trizolate) was designed, based on the self-assembly under hydrothermal conditions, and it displays properties of single-molecule magnets (SMMs), white-light emission and ferroelectricity. Studies of static and dynamic magnetism reveal the SMMs behaviour of 1 with energy barrier Ueff = 43.22(8) K. Furthermore, the strategy of a dichromatic mixture of blue (bpt−) and yellow (Dy3+) emissive colours was utilized to obtain white-light emission through modulation of the excitation wavelength. This strategy has been worked up to create lanthanide-based fluorescent molecular magnets recently. Moreover, ferroelectricity, a “plus” feature, was added to the cluster as a result of the polar point group C2v. [ABSTRACT FROM AUTHOR]

Supertetrahedral clusters: A family of lanthanide oxide supertetrahedral T3 {Ln20} clusters (Ln=Tb, Dy, Ho, Er; see figure) were obtained from the solvothermal reaction of lanthanide(III) salts with polytriazolate ligands that could be methylated and oxidized in situ. [ABSTRACT FROM AUTHOR]

Four single-phase isostructural mononuclear complexes (HNEt3)[DyxYb1−x(bpyda)2]·3H2O (x = 1 (1), 0 (2), 0.367 (3), 0.135 (4), bpyda = 2,2′-bipyridine-6,6′-dicarboxylate) show characteristics of controllable slow relaxation and photoluminescence. The molecular hybrids 3 and 4 exhibit the Orbach process for the DyIII component and a mixture of direct and Raman processes for the YbIII component. The presence of paramagnetic YbIII enhances the relaxation time of the DyIII component, originating from the suppression of the direct process/QTM. The correlation between photoluminescence, static susceptibilities and dynamic magnetic relaxation in the hybrid species was also analysed by comparing the energy gap between the ground and first excited states to the energy barrier. [ABSTRACT FROM AUTHOR]

Multifunctional material: A remarkable case of a single‐molecule magnet that demonstrates white‐light emission and ferroelectricity was observed in a butterfly‐shaped chiral DyIII4 cluster, [Dy4(μ‐bpt)4(μ3‐OH)2(μ‐OMe)2(NO3)4]⋅3 MeOH (bpt=3,5‐bis(pyridin‐2‐yl)‐1,2,4‐trizolate, see figure). [ABSTRACT FROM AUTHOR]

The pentagonal bipyramidal single‐ion magnets (SIMs) are among the most attractive prototypes of high performance single‐molecule magnets (SMMs). A fluorescence‐active phosphine oxide ligand is introduced, and by combining dynamic magnetic measurements, optical characterization, and ab initio calculations, the magneto‐optical correlation of a high‐performance pseudo‐D5h DyIII SIM with large Ueff = 508(2) K and high magnetic hysteresis temperature of 19 K, [Dy(CyPh2PO)2(H2O)5]Br3⋅2 (CyPh2PO)⋅EtOH⋅3 H2O (CyPh2PO=cyclohexyl(diphenyl)phosphine oxide) was studied. This work provides a deeper insight into the rational design of promising molecular magnets. More information can be found in the Full Paper by M.‐L. Tong, J.‐L. Liu, et al. on page 5708 ff. [ABSTRACT FROM AUTHOR]

The article presents a study on the synthesis, structure, and photophysical properties of a heteronuclear gold(I)-silver(I) cluster that is emissive in solution at room temperature. It notes that the report is the first regarding the luminescence from a gold(I) carbonium system. It cites the findings of the single crystal x-ray structural analysis on the cationic part of the complexes. It mentions that complex 2 is brightly emissive while complex 3 is soluble in polar solvents like chloroform.

Single-molecule magnets (SMMs) are regarded as a class of promising materials for spintronic and ultrahigh-density storage devices. Tuning the magnetic dynamics of single-molecule magnets is a crucial challenge for chemists. Lanthanide ions are not only highly magnetically anisotropic but also highly sensitive to the changes in the coordination environments. We developed a feasible approach to understand parts of the magneto-structure correlations and propose to regulate the relaxation behaviors via rational design. A series of Co(II)-Dy(III)-Co(II) complexes were obtained using in situ synthesis; in this system of complexes, the relaxation dynamics can be greatly improved, accompanied with desolvation, via single-crystal to single-crystal transformation. The effective energy barrier can be increased from 293 cm−1 (422 K) to 416 cm−1 (600 K), and the tunneling relaxation time can be grown from 8.5 × 10−4 s to 7.4 × 10−2 s. These remarkable improvements are due to the change in the coordination environments of Dy(III) and Co(II). Ab initio calculations were performed to better understand the magnetic dynamics. [ABSTRACT FROM AUTHOR]

On account of the scarcity of molecules with a satisfactory second near-infrared (NIR-II) response, the design of high-performance organic NIR photothermal materials has been limited. Herein, we investigate a cocrystal incorporating tetrathiafulvalene (TTF) and tetrachloroperylene dianhydride (TCPDA) components. A stable radical was generated through charge transfer from TTF to TCPDA, which exhibits strong and wide-ranging NIR-II absorption. The metal-free TTF-TCPDA cocrystal in this research shows high photothermal conversion capability under 1064 nm laser irradiation and clear photothermal imaging. The remarkable conversion ability-which is a result of twisted components in the cocrystal-has been demonstrated by analyses of single crystal X-ray diffraction, photoluminescence and femtosecond transient absorption spectroscopy as well as theoretical calculations. We have discovered that space charge separation and the ordered lattice in the TTF-TCPDA cocrystal suppress the radiative decay, while simultaneously strong intermolecular charge transfer enhances the non-radiative decay. The twisted TCPDA component induces rapid charge recombination, while the distorted configuration in TTF-TCPDA favors an internal non-radiative pathway. This research has provided a comprehensive understanding of the photothermal conversion mechanism and opened a new way for the design of advanced organic NIR-II photothermal materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

High-nuclear lanthanide clusters have shown great potential for the administration of high-dose mononuclear gadolinium chelates in magnetic resonance imaging (MRI). The development of high-nuclear lanthanide clusters with excellent solubility and high stability in water or solution has been challenging and is very important for expanding the performance of MRI. We used N -methylbenzimidazole-2-methanol (HL) and LnCl 3 ·6H 2 O to synthesize two spherical lanthanide clusters, Ln 32 (Ln = Ho, Ho 32 ; and Ln = Gd, Gd 32 ), which are highly stable in solution. The 24 ligands L - are all distributed on the periphery of Ln 32 and tightly wrap the cluster core, ensuring that the cluster is stable. Notably, Ho 32 can remain highly stable when bombarded with different ion source energies in HRESI-MS or immersed in an aqueous solution of different pH values for 24 h. The possible formation mechanism of Ho 32 was proposed to be Ho(III), (L) - and H 2 O → Ho 3 (L) 3 /Ho 3 (L) 4 → Ho 4 (L) 4 /Ho 4 (L) 5 → Ho 6 (L) 6 /Ho 6 (L) 7 → Ho 16 (L) 19 → Ho 28 (L) 15 → Ho 32 (L) 24 /Ho 32 (L) 21 /Ho 32 (L) 23 . To the best of our knowledge, this is the first study of the assembly mechanism of spherical high-nuclear lanthanide clusters. Spherical cluster Gd 32 , a form of highly aggregated Gd(III), exhibits a high longitudinal relaxation rate (1 T, r 1 = 265.87 mM -1 ·s -1 ). More notably, compared with the clinically used commercial material Gd-DTPA, Gd 32 has a clearer and higher-contrast T 1 -weighted MRI effect in mice bearing 4T1 tumors. This is the first time that high-nuclear lanthanide clusters with high water stability have been utilized for MRI. High-nuclear Gd clusters containing highly aggregated Gd(III) at the molecular level have higher imaging contrast than traditional Gd chelates; thus, using large doses of traditional gadolinium contrast agents can be avoided., (© The Author(s) 2023. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Protein S-nitrosylation is one of the most important post-translational modifications, a well-grounded understanding of S-nitrosylation is very significant since it plays a key role in a variety of biological processes. For an uncharacterized protein sequence, it is a very meaningful problem for both basic research and drug development when we can firstly identify whether it is a S-nitrosylation protein or not, and then predict the specific S-nitrosylation site(s). This work has proposed two models for identifying S-nitrosylation protein and its PTM sites. Firstly, three kinds of features are extracted from protein sequence: KNN scoring of functional domain annotation, PseAAC and bag-of-words based on the physical and chemical properties of amino acids. Secondly, the synthetic minority oversampling technique is used to balance the data sets, and some state-of-the-art classifiers and feature fusion strategies are performed on the balanced data sets. In the five-fold cross-validation for predicting S-nitrosylation proteins, the results of Accuracy (ACC), Matthew's correlation coefficient (MCC) and area under ROC curve (AUC) are 81.84%, 0.5178, 0.8635, respectively. Finally, a model for predicting S-nitrosylation sites has been constructed on the basis of tripeptide composition (TPC) and the composition of k-spaced amino acid pairs (CKSAAP). To eliminate redundant information and improve work efficiency, elastic nets are employed for feature selection. The five-fold cross-validation tests have indicated the promising success rates of the proposed model. For the convenience of related researchers, the web-server named "RF-SNOPS" has been established at http://www.jci-bioinfo.cn/RF-SNOPS.