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1, 4, 5, 8‐naphthalene diimide (NDI)‐based MOFs, due to their tunable structures and properties, have shown promising applications in photochromism, photocatalysis, electrocatalysis, photothermal therapy, etc. Herein, using an L‐alanine modified NDI ligand, i.e. N, N′‐bis(L‐alanine)naphthalenediimide (AlaNDI), a novel Cd‐NDI Cd (AlaNDI)(H2O)]·DMF·H2O (complex 1) was constructed under solvothermal conditions, which has an obvious different structure with the previously reported ones. Structural analysis shows that the packing structure of complex 1 consists of two adjacent Cd atoms sharing two AlaNDI ligands, forming a dimetallic building block [Cd2O8]. Each building block connects a total of four AlaNDI ligands, where two Cd atoms are bridged by two ligands. The building blocks are interconnected by ligands to form a two‐dimensional layered structure. Based on the features of the NDI skeleton, it was found that complex 1 possesses multiple stimulus responses involving sensitivity to light: a reversible photochromism property and good photocatalytic degradation activity against various dyes, especially against cationic dyes crystal violet (CV), methyl violet (MV), and Janus green B (JGB). In addition, the stimulus‐response mechanism was investigated by control experiments. It is revealed that the photocatalytic active species may be related to h+ and •OH. [ABSTRACT FROM AUTHOR]

The heteronuclear d-f coordination complexes [Er2Zn2(C6H5COO)10(phen)2] (1), [Ho2Zn2(C6H5COO)10(phen)2] (2), [Pr3Zn6(C6H5COO)21(phen)3] (3), [ErCd(C6H5COO)5(phen)·H2O] (4), [Ho2Cd3(C6H5COO)12(phen)2] (5), [EuCd2(C6H5COO)7(phen)2] (6) (C6H5COOH = benzoic acid;phen = 1,10-phenanthroline) were synthesized by hydrothermal methods, and their structures were studied by single-crystal X-ray diffraction. Complexes 1, 2, 4, and 5 crystallize in the triclinic space group P1 and complexes 3 and 6 in the monoclinic space group C2/c. The room temperature IR, UV/Vis/NIR ab-sorption, and emission spectra of the six complexes were determined and assigned. In the visible and NIR regions, the emission spectra of complexes show characteristic bands of corresponding LnIII ions, which are attributed to the sensitization from the d block (Zn/Cd-ligand section) and ligands. In comparison with isolated LnIII ions, the NIR emission bands of complexes 1-5 exhibit shifting, broadening and splitting, which are also present in their UV/Vis/NIR absorption spectra. Thus, the two spectra of complexes can evidence each other. [ABSTRACT FROM AUTHOR]

Abstract: Four Ln3+ coordination complexes with the formulas [Ln(p-toluylate)2(Ac)(H2O)] n (Ln=Ho 1, Yb 2) and {[Ln2(OOCCH2CH2COO)3(H2O)4]·6H2O} n (Ln=Ho 3, Yb 4) were synthesized hydrothermally. Their structures were determined by single-crystal X-ray diffraction. Complexes 1 and 2 are isomorphic and form infinite 2D network structures comprising p-toluylate and acetate (Ac–) moieties. Complexes 3 and 4 are also isomorphic and possess infinite 2D structures in which succinate acts as bridging ligands that are connected to a 3D hydrogen bonding network by O–H…O hydrogen bonds. Solid-state IR and UV-Vis-NIR spectra, excitation and emission spectra were determined for the four complexes at room temperature. Complexes 1 and 2 exhibit characteristic NIR emission bands of Ln3+ ions but these are shifted and split relative to the theoretical positions. This is also evident for their UV-Vis-NIR spectra. The influence of ligands on enhancing the NIR luminescence of Ln3+ ions in complexes is discussed. [Copyright &y& Elsevier]

Hydrothermal reaction of the multidentate organic ligand (H 6 TTHA) with indium chloride (InCl 3 ) produced a highly stable 3D luminescent indium-organic framework [In 2 (OH) 2 (H 2 TTHA)(H 2 O) 2 ] n (1). Complex 1 exhibits remarkable luminescent properties, especially the multifunction sensitivity and selectivity for detecting Ru 3+ , UO 2 2+ ; as well as small biomolecules thiamines (TPP, TMP, and TCl) based on a "turn-off" manner. In particular, the pyrophosphate groups of TPP and the phosphate groups of TMP could further affect the quenching rate, leading to different luminescent responds. In addition, we also discussed and proved the luminescence quenching mechanism in detail through comparative test and PXRD characterization. Therefore, complex 1 could be used as a kind of excellent luminescence sensor to detect Ru 3+ , UO 2 2+ , and thiamines (TPP, TMP, and TCl).

Five Zn( [II)) and Cd(II) coordination complexes, [Zn(NA)2 (H2O)4](1), [Zn(INA)2 (H2O)4](2), [Zn(2,2'-bi-py)2 (SCN)2](3), [Cd(INA)2 (H2O)4](4) and [Cd(phen)2(NO3)](5) (HNA=nicotinic acid, HINA=isonicotinic acid, 2, 2'-bipy=2,2'-bipyridine, phen=1,10-phenanthroline), were synthesized through constant temperature magnetic stirrer or hydrothermal method, and their single-crystal structures were determined by X-ray diffraction. The authors measured the IR, UV-Vis-NIR and fluorescence spectra of the complexes and analyzed their photophysical properties. At room temperature in the solid state the five complexes can show strong fluorescence, i.e., lamdamax(em)=362 nm (lamda(ex)=330 nm), (1); lamdamax(em)=424 nm (lamda(ex)=330 nm), (2); lamdamax(em)=442 nm (lamda(ex)=380 nm), (3); lamdamax(em)=424 nm (lamda(ex)=330 nm), (4); lamda(em max)=456 nm (lamda(ex)=360 nm), (5), and complex (5) can emit phosphorescence upon excitation at 360 nm (lamdamax (pl)=546 nm, tau=10 ms). But the organic ligands are different, which lead to the luminescence property of complexes originating from different charge transfer. Compared with the relevant ligands (lamdamax (em)=380 nm, HNA; lamda(em max)=541 nm, 2,2'-bipy), the fluorescence emissions of complex (1) and (3) show a blue-shift which mainly comes from the ILCT (intraligand charge transfer) and at the same time exists L-->M(4S) transfer. The emissions of complex (2) and (4) come from LMCT (ligand-to-metal charge transfer) and show red-shift compared to that of free ligand (lamdamax(em)=337 nm, HINA). For complex (5), the appearance and position of its emission are different from those of the ligand (lamdamax(em)=381 nm, phen), which is attributed to LLCT (ligand-to-ligand charge transfer) and LMCT.