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Two novel molecules TAP and TAH with pronounced reversible halochromic properties have been synthesized and fully characterized. Their butterfly‐like structures have been confirmed through single‐crystal X‐ray diffraction. Their UV‐Vis absorption after protonation dramatically red‐shifted with naked‐eye‐visible color change in a very dilute concentration of 10−5 M. Note that the original color of the solution can be recovered after the neutralization with a base. [ABSTRACT FROM AUTHOR]

Although there are many works focusing on tuneable photoluminescence(PL) character of Manganese(Mn)‐doped perovskite nanocrystals(PNCs), systematically studying the influence of cations (such as Zn2+, Sn2+ and Mg2+) and anions (such as Cl−) on the Mn emission intensity is uncultured. Here, based on a modified method, hydrochloric acid(HCl), the single and simplest Cl− precursor, is firstly used to tune the Mn emission intensity of PNCs prepared under high temperature. By limiting the Cl sources and introducing other cations (Zn2+, Sn2+ and Mg2+) in the reaction system, the Mn emission intensity of final PNCs could be tuned negatively. Besides, this is the first time to realize co‐doping Zn and Mn ions into PNCs during the formation of PNCs. In addition, the as‐prepared stable doped PNCs have been used as active materials in light emitting devices(LEDs), which display orange emission. Based on a modified synthesis route, the Cl source in the CsPbCl3 PNCs could be independent from the Pb source. Simply changing the amount of HCl precursor, the intensity of Mn emission could be tuned positively. By inducing other cations such as Zn, Sn and Mg ions to compete with Mn ions or prevent the Mn doping process, the intensity of Mn emission could be tuned negatively. [ABSTRACT FROM AUTHOR]

Searching novel haloplumbate building units to construct three‐dimensional (3D) frameworks is very important and highly desirable because such materials would possess new physical properties and potential applications. Here, by employing tetrakis(N‐imidazolemethylene)methane(TIMM) as a structure‐directing agent, the first 3D haloplumbate framework constructed from unprecedented Lindqvist‐like highly coordinated [Pb6Br25]13− nanoclusters has been successfully prepared under hydrothermal condition, where all Pb2+ centres in [Pb6Br25]13− nanoclusters adopt seven‐/eight‐coordinated configurations. The as‐obtained material is a wide‐gap semiconductor (≈3.1 eV) and can be stable up to 320 °C. More importantly, this material has been demonstrated to show temperature‐dependent emission. Our results could provide a new strategy to explore novel metal–halide open‐framework materials. Mind the gap: The first 3D haloplumbate framework constructed from unprecedented Lindqvist‐like highly coordinated [Pb6Br25]13− nanoclusters was successfully obtained. The as‐prepared material is a wide‐gap semiconductor and shows an interesting temperature‐dependent photoluminescence. [ABSTRACT FROM AUTHOR]

A durable luminescent imidazolium-based main-chain ionic polymer (IMIP-Br) was prepared by a facile quaternization reaction of tri(4-imidazolylphenyl)amine and 1,2,4,5-tetrakis(bromomethyl)benzene. IMIP-Br can not only detect Cr2O72− rapidly and estimate its concentration in water, but also capture Cr2O72− quickly via anion exchange. The tremendous exchange capacity of 318 mg g−1 and remarkable efficiency of 92.6% are achieved using an equivalent amount of IMIP-Br. The separation and recycling procedures are simplified by the integration of Fe3O4 particles and IMIP-Br. The resultant IMIP-Fe shows outstanding enrichment ability, good regenerative ability and superior recyclability for removal of Cr2O72−. The combination of promising removal performances and simple magnetic separation endows IMIP-Fe with great promises for capture and separation of Cr2O72− from contaminated water systems. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of 1,4-bis(imidazol-1-yl)benzene (bimb) and either 5-hydroxyisophthalic acid (HO-H2ip) or 5- methoxyisophthalic acid (MeO-H2ip), as well as transition metal salts, gave rise to six new coordination polymers: [Zn2(bimb)(H2O)(HO-ip)2]n (1), [Zn(bimb)(MeO-ip)]n·(H2O)n (2), [Mn2(bimb)2(HO-ip)2]n (3), [Mn2(bimb)2(H2O)2(MeOip) 2]n (4), [Cu2(bimb)2(MeO-ip)2]n·(H2O)3n (5), and [Co- (bimb)(H2O)(MeO-ip)]n·(DMF)0.5n·(H2O)n (6). Their structures have been defined by single-crystal X-ray diffraction analyses, IR spectra, elemental analyses and thermogravimetric analyses. Complex 1 is a 2D coordination network consisting of μ-oxygen-bridged dinuclear ZnII units, whereas 2 is an interdigitating 2D layer. ZnII ions in 1 and 2 have a distorted tetrahedral geometry, and two independent HO-ip and two bimb moieties in the dinuclear unit of 1 form π···π stacking interactions. Complexes 3 and 4 are 2D layers consisting of dinuclear MnII carboxylate units; bimb in an anti conformation serves as an exo-bidentate ligand in 3, whereas in 4 it acts as a terminal ligand, filling void space. Bis-monodentate MeO-ip in 5 connects CuII ions into a 3D coordination network, whereas MeO-ip in 6 bridges between two CoII ions to form a 2D layer, with the strong hydrogen bonds between water molecules of the adjacent 2D layers generating a 2D supramolecular bilayer. The dinuclear MnII units in 3 and 4 are well separated by organic ligands, and make up the basic magnetic units. Temperature-dependent magnetic susceptibility analyses show the existence of antiferromagnetic interaction in 3 and 4. [ABSTRACT FROM AUTHOR]

Dichromate capture: A 3D cationic metal–organic framework consisting of distorted octahedral and tetrahedral cages was constructed by using AgI and 4,4′‐bis(1,2,4‐triazole). The complex exhibits fast exchange, high trapping capacity, and good selectivity for Cr2O72− through single‐crystal to single‐crystal transformation. The complex also features a bluish violet luminescence that is distinctly quenched after Cr2O72− exchange. [ABSTRACT FROM AUTHOR]

The reaction of bis- or tris-chelating nitrogen-containing ligands (L1-L5) with CuI gave rise to five coordination complexes consisting of Cu2I2 dimeric units. L1 in complex 1 adopts a cis conformation and links Cu2I2 into a dinuclear structure. L2 and L3 in complexes 2 and 3 exhibit a trans conformation, and the alternative linkage of L2 or L3 and Cu2I2 results in the formation of a 1D chain. In complex 4, two pyrazolyl-pyridine units of L4 at the same side of the central phenyl ring are connected to Cu2I2 forming a tetranuclear macrocycle, and the third pyrazolyl-pyridine unit at the other side of the central phenyl ring further links the macrocycle into a 1D chain. L5 bridges Cu2I2 in a cis conformation forming a tetranuclear complex, which is very different from 1 owing to the difference of the electronic property between pyrazolyl and triazolyl rings. The coordination nitrogen atoms in two pairs of ortho-positioned nitrogen-containing chelating rings in L1 and L5 are directed toward opposite and the same directions, respectively. Complexes 1- 4 containing pyrazolyl-pyridine units showed luminescence whereas no clear emission was observed in complex 5 containing triazolyl-pyridine units, despite the fact that they were investigated under the same conditions. The application of complexes 1- 5 in the copper(I)-catalyzed Ullmann cross-coupling reaction and azide-alkyne cycloaddition reaction was preliminarily evaluated. [ABSTRACT FROM AUTHOR]

Although there are many works focusing on tuneable photoluminescence(PL) character of Manganese(Mn)‐doped perovskite nanocrystals(PNCs), systematically studying the influence of cations (such as Zn2+, Sn2+ and Mg2+) and anions (such as Cl−) on the Mn emission intensity is uncultured. Here, based on a modified method, hydrochloric acid(HCl), the single and simplest Cl− precursor, is firstly used to tune the Mn emission intensity of PNCs prepared under high temperature. By limiting the Cl sources and introducing other cations (Zn2+, Sn2+ and Mg2+) in the reaction system, the Mn emission intensity of final PNCs could be tuned negatively. Besides, this is the first time to realize co‐doping Zn and Mn ions into PNCs during the formation of PNCs. In addition, the as‐prepared stable doped PNCs have been used as active materials in light emitting devices(LEDs), which display orange emission. Based on a modified synthesis route, the Cl source in the CsPbCl3 PNCs could be independent from the Pb source. Simply changing the amount of HCl precursor, the intensity of Mn emission could be tuned positively. By inducing other cations such as Zn, Sn and Mg ions to compete with Mn ions or prevent the Mn doping process, the intensity of Mn emission could be tuned negatively. [ABSTRACT FROM AUTHOR]

Preparing low-dimensional perovskite materials with novel building units is highly desirable because such materials have already been demonstrated to show unusual physical properties. In this report, we first reported a new and unusual two-dimensional perovskite framework, [B(HIm) 4 ] 4 Pb 13 Br 38 (1), constructed from novel Lindqvist-type [Pb 6 Br 19 ] 7- nanoclusters. The as-prepared material shows good water resistance and chemical/heat stability. More importantly, 1 has been proven to exhibit temperature/excitation-wavelength-dependent emission. A possible mechanism has been provided.

Searching novel haloplumbate building units to construct three-dimensional (3D) frameworks is very important and highly desirable because such materials would possess new physical properties and potential applications. Here, by employing tetrakis(N-imidazolemethylene)methane(TIMM) as a structure-directing agent, the first 3D haloplumbate framework constructed from unprecedented Lindqvist-like highly coordinated [Pb 6 Br 25 ] 13- nanoclusters has been successfully prepared under hydrothermal condition, where all Pb 2+ centres in [Pb 6 Br 25 ] 13- nanoclusters adopt seven-/eight-coordinated configurations. The as-obtained material is a wide-gap semiconductor (≈3.1 eV) and can be stable up to 320 °C. More importantly, this material has been demonstrated to show temperature-dependent emission. Our results could provide a new strategy to explore novel metal-halide open-framework materials., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Success in obtaining higher-order twistarenes with precise structures is very important for fundamentally understanding the relationship between the structures and physical properties/optoelectronic applications. In this research, by using the advantages from a retro-Diels-Alder process (clean reaction) and the cross-conjugated nature of the pyrene unit, a novel dodeca-twistarene was prepared for the first time. Its structure, confirmed by single-crystal XRD analysis, indicates that it possesses a twisted angle (≈30°), and two neighboring molecules in the crystal lattice are perpendicular to each other because of the twisted character and the strong intermolecular CH-π interactions. However, its basic physicochemical properties suggest its instability in air derives from its elevated HOMO energy level, although NICS calculations confirm that the pyrene units contribution poorly to the π conjugation of the overall molecule., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Reactions of 5-nitroisophthalic acid (NO2 -H2 ip), 1,4-bis(imidazol-1'-yl)butane (bimb), and Ni(NO3 )2 ⋅6 H2 O gave rise to four metal-organic frameworks (MOFs), [Ni2 (NO2 -ip)2 (bimb)1.5 ]n (1), [Ni4 (NO2 -ip)3 (bimb)2 (OH)2 (H2 O)]n ⋅(CH3 CH2 OH)0.5 n (2), [Ni(NO2 -ip)(bimb)1.5 (H2 O)]n ⋅(H2 O)n ⋅(CH3 CH2 OH)0.5 n (3), and [Ni(NO2 -ip) (bimb)(μ-H2 O)]n ⋅(H2 O)n (4). The metal/ligand ratio, pH value, and solvent exerted a subtle but crucial influence on the formation of complexes 1-4, which possess different visual color and crystal structures. Complex 1 exhibits a twofold interpenetrating 3D pillared bilayer framework composed of binuclear and mononuclear Ni(II) units, whereas complex 2 is a 3D chiral network that consists of asymmetric tetranuclear Ni(II) units. Complexes 3 and 4 are 3D layer-pillared frameworks that consist of mononuclear Ni(II) ions and a 3D six-connected network of μ-water-bridged dinuclear Ni(II) units, respectively. Interestingly, achiral 4 can be transformed into chiral 2 by using a solvent-mediated single-crystal-to-single-crystal process without any chiral auxiliary. Magnetic analyses of 2 and 4 show the occurrence of antiferromagnetic interactions. Complex 3 is difficult to obtain directly as a single solid phase, but it can be homogeneously formed by solvent-mediated transformations from 1, 2, and 4., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Dichromate capture: A 3D cationic metal-organic framework consisting of distorted octahedral and tetrahedral cages was constructed by using Ag(I) and 4,4'-bis(1,2,4-triazole). The complex exhibits fast exchange, high trapping capacity, and good selectivity for Cr2 O7 (2-) through single-crystal to single-crystal transformation. The complex also features a bluish violet luminescence that is distinctly quenched after Cr2 O7 (2-) exchange., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The reaction of bis- or tris-chelating nitrogen-containing ligands (L1-L5) with CuI gave rise to five coordination complexes consisting of Cu 2 I 2 dimeric units. L1 in complex 1 adopts a cis conformation and links Cu 2 I 2 into a dinuclear structure. L2 and L3 in complexes 2 and 3 exhibit a trans conformation, and the alternative linkage of L2 or L3 and Cu 2 I 2 results in the formation of a 1D chain. In complex 4, two pyrazolyl-pyridine units of L4 at the same side of the central phenyl ring are connected to Cu 2 I 2 forming a tetranuclear macrocycle, and the third pyrazolyl-pyridine unit at the other side of the central phenyl ring further links the macrocycle into a 1D chain. L5 bridges Cu 2 I 2 in a cis conformation forming a tetranuclear complex, which is very different from 1 owing to the difference of the electronic property between pyrazolyl and triazolyl rings. The coordination nitrogen atoms in two pairs of ortho-positioned nitrogen-containing chelating rings in L1 and L5 are directed toward opposite and the same directions, respectively. Complexes 1-4 containing pyrazolyl-pyridine units showed luminescence whereas no clear emission was observed in complex 5 containing triazolyl-pyridine units, despite the fact that they were investigated under the same conditions. The application of complexes 1-5 in the copper(I)-catalyzed Ullmann cross-coupling reaction and azide-alkyne cycloaddition reaction was preliminarily evaluated., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)