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The first eight-coordinated trivalent lanthanide complexes with an achiral ligand 6,7-dicyanodipyridoquinoxaline (dicnq), [DyCl(3)(dicnq)(2)](n) (1 and 1') were found to exhibit spontaneous chiral resolution, SHG active (two times that of KDP) and blue luminescence.

Solid-state materials with adjustable luminescence properties have always been a research hotspot due to their potential applications in optical data recording, display and ink-free printing. Further research on the multiform light-controlled luminescent switches will create a new perspective. We synthesized two isostructural compounds, namely [Me(ipbp)Cl] H2O (ipbp = 1-(3,5-dicarboxyphenyl)-4,4′-bipyridinium, Me = Cd (1), Me = Zn (2)). In the solid-state, they not only show excitation-wavelength-dependent photoluminescence emission in a wide spectral range but also exhibit good time-dependent photoluminescence emission. This study could provide a broad perspective for the development of multiform light-controlled luminescent switches. [ABSTRACT FROM AUTHOR]

The synergy of unusual X-aggregation induced luminescent chromophores and heavy Pb(II) ions has facilitated excellent X-ray scintillation of two structurally similar Pb-SMOFs, which are heat-resistant due to solvent-free lattices. Owing to their higher Pb(II) contents, Pb-SMOFs with larger X-ray absorption coefficients are more sensitive for X-ray dosage detection than powdered CsPbBr3. [ABSTRACT FROM AUTHOR]

Efficient cathode-ray scintillating metal–organic frameworks are constructed from a π-conjugated luminescent motif and light Ca(II) ions. The luminescence self-quenching pathway has been effectively hindered through coordination. In situ vacuum ultraviolet fluorescent spectra have shown the excitons recombining in the scintillation process for the first time. [ABSTRACT FROM AUTHOR]

In this work, we report a new mechanoresponsive luminescent Cd(ii) coordination polymer that exhibits a sensitivity to mechanical stimulation. The luminescence colour changed gradually from weak yellowish-green to bright cyan in response to different grinding sizes, thereby showing interesting mechanochromic properties, namely a grinding-enhanced luminescence and good crystalline maintenance ability. [ABSTRACT FROM AUTHOR]

Two new lead(ii) coordination polymers, [Pb(NO3)(tzib)]n (1) and [Pb(tzib)2]n (2), were successfully synthesized from the reaction of a rigid ligand 1-tetrazole-4-imidazole-benzene (Htzib) and lead(ii) nitrate in different solvents. The obtained polymers have been characterized by single-crystal X-ray diffraction analyses, which show that both polymers feature 2D layer structures. The inorganic anion nitrate in 1 shows a μ2–κO3:κO3 bridging mode to connect adjacent lead ions into a zigzag chain, and then the organic ligands tzib− join the neighboring chains into a 2D layer by a μ3–κN1:κN2:κN6 connection mode. In 2, there are two different bridging modes of the tzib− ligand: μ3–κN1:κN2:κN6 and μ3–κN1:κN6 to coordinate the lead ions into a 2D layer structure. Interestingly, both polymers displayed broadband emissions covering the entire visible spectra, which could be tunable to near white-light emission by varying excitation wavelengths. [ABSTRACT FROM AUTHOR]

Three air-stable tetrahedral manganese(ii) dihalide complexes [MnX2(DPEPO)] (DPEPO = bis[2-(diphenylphosphino)phenyl]ether oxide; X = Cl, Br and I) were prepared. All of the obtained compounds were structurally characterized by single-crystal X-ray diffraction analyses, which reveal that they crystallize in centrosymmetric space groups and feature an isolated mononuclear structure with Mn2+ in a tetrahedral environment. Interestingly, these complexes show excellent photoluminescent performance in neat solid form, with the highest total quantum yield (Φtotal) of up to 70% recorded for the dibromide complex. Intense green flashes of light could be observed by the naked eye when rubbing the manganese(ii) complexes. [ABSTRACT FROM AUTHOR]

Abstract: Spontaneous resolution in solvothermal reactions through tuning the volume of the templating and space-filling agents (quaternary ammonium cations) lead to three novel halogeno(cyano)cuprates [R4N][Cu(CN)X] (R=Et, X=Cl, 1; R=Et, X=Br, 2; R=Bu, X=I, 3), which all consist of 1-D helical chains. Compounds 1 and 2 reveal to be mesomeric structures while compound 3 exhibits a nonracemic enantiopure topology. Luminescent studies indicate that all three compounds are potential materials for efficient luminescent materials. [Copyright &y& Elsevier]

Five coordination polymers 1–5with four types of (4,4) layers havebeen synthesized through anew strategy of designing their crystal structures based on (4,4)topology. Compound [Co(adc)(bpp)(H2O)]n(1) presents a 2-D structurewith 2-fold homointerpenetration of layer A, while the2-D compound {[Ni(adc)(bpp)2(H2O)]2·bpp}n(2) presents 2-fold heterointerpenetration of layer Bandlayer C. Compound [Zn(adc)(bpp)·DMF]n(3) displays a typical 2-D→ 3-D parallel interpenetrating structure of layer D. Compounds [Ni(Cladc)(bpp)(H2O)]n(4) and [Co(Cladc)(bpp)(H2O)]n(5) are isomorphousand display similar structures to 1. (H2adc= 4,4′-azodibenzoic acid, ClH2adc = 3,3′-dichloro-4,4′-azodibenzoicacid, bpp = 1,3-di(4-pyridyl)propane, DMF = N,N-dimethylformamide). Luminescence propertiesand thermal stabilities of 1–5havebeen explored. [ABSTRACT FROM AUTHOR]

Abstract: A novel triazole-bridging polynuclear silver(I) complex, [Ag4(ptr)6](NO3)4 ·4H2O (1), was synthesized with (m-phenol)-1,2,4-triazole (ptr), which is the first discrete tetranuclear complex containing 4-substituted triazoles. The compound features blue fluorescence with a broad emission at 432nm excited at 363nm, possibly originating from the π–π∗ transition of the triazole ring. [Copyright &y& Elsevier]

Abstract The assembly of a carboxylate substituted anthracene derivative with barium(II) salt yielded a 3D luminescent metal-organic framework [Ba 2 (adda) 2 (H 2 adda)(H 2 O) 2 ] n 1 (H 2 adda = (2 E ,2′ E)-3,3′-(anthracene-9,10-diyl) diacrylic acid), which was structurally characterized by elemental analysis, powdered and single-crystal X-ray diffraction. Compound 1 exhibits a "turn on" luminescence response toward 4-nitrobenzoic acid (4-NBA) different from most nitroaromatic compounds displaying a "turn-off" luminescence stimulus. Increasing luminescence intensities with addition of 4-NBA in 1 dispersed in DMF are attributed to the dissociation of H 2 adda, evidenced by 1H NMR. Compound 1 is effective as a potential 4-NBA detector by establishing the relationship between the luminescence intensity of 1 and the molar concentration of 4-NBA. Graphical abstract A barium-based 3D luminescent MOF [Ba 2 (adda) 2 (H 2 adda)(H 2 O) 2 ] n 1 (H 2 adda = (2 E ,2′ E)-3,3′-(anthracene-9,10-diyl) diacrylic acid) was successfully obtained under the solvothermal condition and structurally characterized. Compound 1 displays an unprecedented "turn-on" luminescence response toward 4-NBA and acts as a promising 4-NBA detector. Unlabelled Image Highlights • The assembly of a anthracene derivative ligand H 2 adda with barium(II) salt yielded a 3D MOF [Ba 2 (adda) 2 (H 2 adda)(H 2 O) 2 ] n 1. • Compound 1 dispersed in DMF exhibits a "turn on" luminescence response toward 4-nitrobenzoic acid (4-NBA). • The mechanism of the "turn on" luminescence response of 1 was investigated by dynamic 1H NMR spectra. [ABSTRACT FROM AUTHOR]

A novel open-framework cadmium selenite bromide, [Cd10(SeO3)8Br4]·HBr·H2O (1), has been obtained by a solid-state reaction at 450°C, and the structure has been determined by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in Pbcm of the orthorhombic system: a=10.882(3), b=16.275(5), c=18.728(6)Å, V=3317(2)Å3, R1/wR2=0.0411/0.0659. Compound 1 is characteristic of a novel 3-D open-framework structure, composing ∞ 2[CdSeO3] layers and the pillars of edge-shared CdO3Br2 square pyramids. The lattice water molecules and the HBr molecules locate in the voids of the framework. Optical absorption spectrum of 1 reveals the presence of an optical gap of 1.65eV. Solid-state photoluminescent study indicates that compound 1 exhibits strong violet emission. TG–DSC measurement shows that compound 1 is thermally stable up to 200°C. [ABSTRACT FROM AUTHOR]

Abstract: A series of lanthanide(III) complexes with chelidamic acid ligand, [Ln(C7H2NO5)·3H2O] n ·nH2O (Ln=La (1), Y (2), Sm (3), and Nd (4)), [Gd2(C7H2NO5)3·4H2O] n ·2nH2O (5) and [Ce(C7H2NO5)·1.5H2O] n (6), have been synthesized by hydrothermal method and structurally characterized by single-crystal X-ray diffraction. Complexes 1–4 are isostructural and possess 2D framework. Complex 5 contains two different Gd(III) ions linked through carboxylate group to form a 2D framework. Complex 6 exhibits a (44) topology 2D network. The variable-temperature magnetic properties of 3 and 5 have been investigated. Furthermore, the photoluminescent properties of 1, 2, 3, and 5 at room temperature were also studied. [Copyright &y& Elsevier]

Abstract: Hydrothermal reaction of 1H-tetrazolate-5-ethyl acetate (Htzea), MCl2 (M=Zn, Cd) and NaOH at different reaction temperatures produced three new coordination polymers: 2-D layered polymer [Zn(tza)(H2O)2] n 1, and 1-D chained supramolecular isomers 2 and 3 formulated as [Cd(tza)(H2O)2] n (H2tza=1H-tetrazolate-5-acetic acid), respectively. In these obtained polymers, tza2− ligand adopts variable coordination modes: μ 3-κN3:κO1:κO2,N1 and μ 3-κN1:κN3:κO2 for 1, and μ 3-κN2:κN1,O2:κO1,O2 for 2 and 3. The effects of reaction temperature and metal centers on the final polymeric frameworks have been discussed. Polymers 1–3 exhibit blue photoluminescence mainly arising from intraligand transitions of tetrazolate rings in tza2− ligand. [Copyright &y& Elsevier]

Abstract: A 1D coordination polymer, {[Cu3(C7H2NO5)2(H2O)7]·2(H2O)} n (1), has been synthesized and characterized by X-ray single-crystal diffraction. The crystal structure of 1 features that distorted square–pyramidal coordination polyhedra composed of Cu atoms and chelidamic acid ligands are interlinked into a 1D polymer, further linked by hydrogen bonds into a 3D network. The optical properties were investigated in terms of diffuse reflectance and fluorescent spectra, which exhibit strong luminescence. The electronic band structure along with the density of states (DOSs) calculated by the DFT method indicate that compound 1 pose an energy band gap of 1.89eV and that the origin of the emission band may be mainly ascribed to metal-to-ligand charge transfer (MLCT) where the electrons are transferred from the Cu-3d to O-2p and C-2p states. [Copyright &y& Elsevier]

Abstract: Systematic survey on the reactions of silver nitrate with H3Ssal ligand (H3Ssal=5-sulfo-salicylic acid) accompanying with different alkali metal ions under alkali conditions leads to two novel luminescent alkali-silver heterometallic sulfonates, [KAg(HSsal)(H2O)3] n (1) with a 3-D structure constructed by [K2O10] binuclear units linking 1-D∞ 1[Ag2(HSsal)2] double chains, [NaAg(HSsal)(H2O)3] n (2) with a 3-D structure constructed by the [Ag2(HSsal)2] dimers connecting 1-D∞ 1[NaO6] chains, and also reveals the coordination strength of the alkali metal cations and Ag+ towards the sulfonate groups with K+ >Na+ >Ag+ >Li+ order. The two compounds show intense blue emissions in both solid state and water solution. [Copyright &y& Elsevier]

Abstract: The first structurally characterized orotato samarium(III) complex, [Sm2(HL)2(ox)(H2O)2] n ·2.5nH2O (1), with a novel bi-layered structure has been synthesized and structurally characterized by X-ray crystallography, in which orotic acid ligands exhibit two coordination modes of μ3-η2κO,O′:η2κO′,N:η1κ″ and μ4-η2κO,O′:η2κO′,N:η1κ″:η1κO‴ for HL2− with the latter being novel coordination mode. The temperature dependence of the magnetic susceptibilities of the title complex reveals that the title complex follow the Curie–Wiess paramagnetic behavior down to 5K. The title complex exhibits strong luminescent emissions based on the f–f transitions of Sm(III) ion and 4G5/2 lifetime. [Copyright &y& Elsevier]

Methacrylate (MAA) is used as electron donor to design a metalloviologen compound, [Zn 2 (MAA) 4 (bipy) 4 ] n (bipy = 4,4′-bipyridine), resulting in the sensitive electron-transfer photochromism. The photoinduced radical lead to luminescence-photoswitching contrast about 1.4 times after the coloration is saturated. [Display omitted] • A new compound is prepared via diffusion method. • Methacrylate is first introduced into the photochromic metalloviologens. • Compound 1 showed photoswitchable luminescence property. A new inorganic − organic hybrid compound [Zn 2 (MAA) 4 (bipy) 4 ] n (1 , MAA = Methacrylate, bipy = 4,4′-bipyridine) with photochromic properties has been synthesized by diffusion method. Upon irradiation, compound 1 turned from colorless to pale purple and new absorption peaks appeared at 380 nm and 548 nm. The luminescence emission of 1 can be modulated through photoinduced electron transfer process, and the luminescence intensity of the colored sample at 476 nm decreased 1.4 times after irradiation. In this study, MAA is first induced into metalloviologen-based hybrid material for photochromism and photomodulated luminescence applications and compound 1 has enriched the family of photoresponsive materials. [ABSTRACT FROM AUTHOR]

A new photochromic inorganic-organic hybrid material [(N -MeIQL)BiCl 4 (1 , N -MeIQL+ = N -methylisoquinolinium) has been solvothermally synthesized. In 1 the N -MeIQL+ cation is obtained by in situ alkylation of isoquinoline in the acidized methanol solution, and it is firstly reported that N -MeIQL+ acts as an organic template for the design and synthesis of photochromic material. Compound 1 exhibits reversible photochromism between colorless and bright yellow. Moreover, compound 1 displays dual-emitting luminescence and the lifetimes of the two emissions at 410 nm and 640 nm were measured to be 0.71 ns and 0.28 ms, respectively, indicating the fluorescence and phosphorescence characteristics. It is notable that unlike the luminescence quenching of normal photochromic materials in the process of photoinduced coloration, and the emission intensity of 1 can be significantly enhanced via electron-transfer photochromism. The studies of electron-transfer photochromism and photomodulated luminescence provide useful insight into the design of new photoresponsive materials. An inorganic-organic hybrid material [(N -MeIQL)BiCl 4 (N -MeIQL+ = N -methylisoquinolinium) exhibits sensitive photochromism between colourless and bright yellow, and displays double emissions with luminescent intensity enchanced in the process of photo-induced coloration. Image 1 • It explores a new inorganic-organic hybrid electron-transfer photochromic material. • N-methylisoquinoline firstly acts as the ligand of photochromic material. • It shows dual-emission of phosphorescence and fluorescence at room temperature. • It is first reported emission intensity enhanced by electron-transfer photochromism. [ABSTRACT FROM AUTHOR]

Four complexes, Ln2(C6H5SO2)6(H2O)3 · 2.25H2O (C6H5SO2 = 2-thiopheneacetic acid, Ln = Ce (1), Pr (2), Nd (3), Sm (4)), have been synthesized with hydrothermal route. The X-ray diffraction analyses reveal that they are characterized by the 1D structure and fluorescence studies show they display interesting luminescent properties in solid state. [Copyright &y& Elsevier]