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A new multistimuli-responsive luminescent material, [Cu8I8(4-dpda)6]n (1) (4-dpda=4-(diphenylphosphino)-N,N-dimethylaniline), has been obtained by combining inorganic Cu8I8 clusters and organic ligands 4-dpda, providing a novel in-/organic hybrid approach as an interesting alternative to all-organic approaches. Compound 1 responds well to thermo and mechanical force independently with color change due to the fact that the stimuli affect frontier molecular orbital and molecular packing modes, respectively.

In this communication, we report a series of high-efficiency full-colour fluorescent materials based on isostructural mixed-lanthanide metal–organic complexes. By varying the stoichiometric ratio of the lanthanide ions, a fluent change of emission colours within the full-colour region was realized and strong white light-emission with a high quantum yield up to 62% was also achieved.

Complexes [Zn(bpdc)(H2O)2] (1) and [Mn(bpdc)(H2O)3]∙2.5H2O (2) were assembled by 2,2′-bipyridine-6,6′-dicarboxylate (H2bpdc) with Zn2+ or Mn2+ under hydro/solvo-thermal conditions. Complexes 1 and 2 are extended from mononuclear to 1D, 2D and 3D supramolecular network step by step with the help of intramolecular weak interactions. The luminescent properties of 1 had been investigated in details, which show intense blue emission with relatively good quantum yield. The 2 displays nonlinear optical (NLO) activity comparable with that of KDP, and exhibits weak antiferromagnetic coupling between the Mn (II) ions by the hydrogen bonds.

Three new lanthanide metal organic frameworks (LnMOFs), [HNMe2][Ln2(m-BDC)3(phen)2] (Ln = Eu 1, Gd 2, Tb 3, m-H2BDC = 1,3-benzenedicarboxylic acid, phen = 1,10-phenanthroline), have been solvothermally synthesized through self-assembly reactions. Complexes 1–3 are isostructural and possess 3D architectures based on the octahedral [Ln2(COO)6] SBUs with a pcu net topology. Photoluminescence measurements show that 1 and 3 are highly emissive at room temperature with quantum yields of 86.87% (at 330 nm) and 85.62% (at 345 nm), respectively, and may be good candidates for light-emitting diodes (LEDs) and light applications. The magnetic properties of 2 and 3 have also been investigated through the measurement of their magnetic susceptibilities over the temperature range of 2–300 K.

A series of novel three-dimensional (3D) 3d-4f heterometallic coordination complexes, [{LnZn(bpdc)2(OAc)(H2O)2}·H2O]n (Ln = Nd (1), Sm (2), Eu (3), Tb (4), Dy (5), Er (6); H2bpdc = 2,2′-bipyridyl-4,4′-dicarboxylic acid; HOAc = acetic acid), have been successfully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. All complexes are isostructural and display new 2-fold interpenetrating (3,6)-connected network topology. The luminescent properties of 1–5 in the solid state at room temperature have been studied in detail. It is the first series of luminescent 3d-4f heterometallic complexes with bpdc2– ligands, and it has been found that the energy transitions from the ligands to Eu3+ and Tb3+ are more effective than those to Sm3+ and Nd3+, and the energy transition from the ligand to Dy3+ is in between. Furthermore, thermogravimetric analysis and powder X-ray diffraction are also investigated.

A stimuli-responsive material with AND logic function was realized by modulating sensitive Cu-Cu interactions, which is quite different from traditional photoinduced electron transfer (PET) strategies. The obtained material not only gets rid of fluid media, but also displays nondestructive, high intensity optical signals and environmentally friendly performances.

By varying the stoichiometric ratio of Eu3+, Tb3+ and Gd3+ ions in a lanthanide metal–organic framework, a mixed-Ln MOF, [Eu0.0040Tb0.0460Gd0.9500(BTB)(DMSO)2]·H2O, has been designed to display white-light emission. In addition, the switch between blue, white, and yellow for this material has been achieved by controlling the energy transfer process.

Pseudo-achiral metal-centre driven spontaneous resolution occurred simultaneously in the formation of two Δ- and Λ-isomers of [CdBa(OBA)2(DMF)(CH3OH)(H2O)]·H2O (H2OBA = 4,4′-oxybis(benzoic acid)), which illustrated a clear relationship between chirality and helicity: the absolute sense of a double-helix made of achiral components is induced by metal centres in the two enantiomeric forms.

Two classical metal clusters, CuI4I4 and CuI6S6, are introduced as functional connecting nodes to construct a novel multi-metal-cluster MOF [(CuI4I4)3(CuI6)2(3-ptt)12]n·24nDEF·12nH2O (1) that incorporate their inherent luminescent properties, induced by their respective metal–metal interactions. These two distinct clusters are combined together for the first time to perform as functional luminophores that display unusual dual emission with both thermochromic luminescence and near-infrared (NIR) character.

The first example of an inorganic-organic composite framework with a 3D inorganic Cd-O-M (M = Cd, Rb) connectivity, featuring a unique {Cd(7)Rb}(n) helix and nanoscale {Cd(16)Rb(4)} and {Cd(18)Rb(2)} rings, has been constructed and structurally characterized. This compound exhibits white-light emission and a wavelength-dependent photochromic response.

A novel strategy is provided in this paper to design multi-stimuli-responsive luminescent materials by taking a multi-responsive chromophore which responds to multiple environmental stimuli instead of constructing multi-chromophore systems. Herein, we have successfully prepared a tri-stimuli-responsive luminescent material, [Cu4I4(4-dpda)4] (1), with reversible and independent thermochromism, mechanochromism and vapochromism simultaneously by applying cuprophilic interactions as a multi-responsive chromophore. The organic ligand 4-dpda is chosen to amplify the perturbation toward metallophilic interations for steric hindrance, and many of the molecular interactions of its multi-phenyl moieties are sensitive to tiny disturbances and will translate the effects to the Cu4I4 core of compound 1. Structural and spectrographic investigations show that the changes in luminescence result from the disturbed cuprophilic interactions.

Two novel 3D porous metal–organic frameworks, {[Zn2(bpt)(btc)]·4H2O}n (1) and {[Cd2(bpt)(btc)(H2O)]·(DMA)2}n (2) (DMA = N,N-dimethylacetamide), were prepared based on 3,5-bis(pyrazinyl)-1,2,4-trizole (Hbpt) with the auxiliary ligand 1,3,5-benzenetricarboxylic acid (H3btc). Complex 1 could be described as a (3,6)-connected binodal 3D network with rutile topology and Schlafli symbol of (4.62)2(42.610.83), where its coordination framework exhibits a high thermal stability up to 420 °C as well as excellent boiling-water resistance. Complex 2 shows a (3,6,8)-connected trinodal 3D framework with a Schlafli symbol of (4.62)2(414.612.82)(44.610.8), which has not been reported previously. Interestingly, the gas-adsorption investigation discloses that complex 1 possesses a high enthalpy of H2 adsorption (9.6 kJ mol−1). Intensive solid-state fluorescence spectra of complexes 1 and 2 have also been determined.

An unusual highly connected 3D framework, [K2Cd3(OBA)4(H2O)2(DMF)2](H2O)2 (1) that contains three windows along separate dimensions, has been constructed from a flexible V-shaped ligand 4,4′-oxydibenzoic acid (H2OBA) and a infinite linear {K2Cd3(COO)8}n cluster under solvothermal conditions. Owing to the existence of a polar Ccarboxyl–Ocore–Ccarboxyl moiety in the ligand and the coordinated hydrophilic DMF molecule, a hydrophilic environment is generated at the pore surface. Compound 1 shows high adsorption capacity for polar molecules, such as methanol (7.83%), ethanol (7.13%) and water (13.37%), but exhibits very low uptake capacity for non-polar molecules like methane (0.49%) and cyclohexane (0.68%). Furthermore, its luminescent properties including the quantum yield and lifetime value have also been investigated.

Two hexanuclear Cu(I) clusters [Cu(I)(3)(4-ptt)(3)](2)·3DMF·3H(2)O (1) and [Cu(I)(4-ptt)](6)·8DMF·7H(2)O (2) (4-Hptt = 5-(pyridin-4-yl)-1H-1,2,4-triazole-3-thiol, DMF = N,N-dimethylformamide), were synthesized and characterized. Compounds 1 and 2 with similar coordination environments are isomers, but their detailed structures are different due to the reaction temperature tuning effect. Both 1 and 2 extend from monomers to 3D supramolecules with the help of hydrogen bonding between the triazole and pyridine from the 4-ptt ligands. The Cu(6)S(6) units of 1 pack in a polydirectional array, while the Cu(6)S(6) units in 2 extend in one direction and link the planes of adjacent ligands to enhance the delocalization of π electrons. Their varied Cu-Cu interactions and individual packing modes cause differences in luminescent and thermostable behaviors. Compound 1 exhibits an unusually long wavelength at about 900 nm and a higher thermal stability; while the emission of 2 splits into two bands (high-energy and low-energy emission bands) as the temperature decreases. Therefore, the emissions of 1 originate from a (3)CC transition, and those of 2 are from a mixture of (3)CC and MLCT.

Two novel dual-emissive coordination polymers [Zn2(Hcpop)2(dpe)(H2O)]n·ndpe (1) and [Zn4(cpop)2(dpe)2(μ-OH)2]n·ndpe (2) (H3cpop = 4-(4-carboxyphenoxy)phthalate acid, dpe = 1,2-di(4-pyridyl)ethylene) have been designed and synthesized as promising luminescent materials, which exhibit tunable fluorescence by varying the excitation wavelength.

Six d10 metal–organic complexes with multipyridine ligands, [Cd(terpy)2](NO3)2·2H2O (1), [Cd(terpy)(NO3)2(H2O)] (2), [Hg(terpy)I2] (3), [Zn(tpt)(NO3)(H2O)2]NO3 (4), [Zn2(tpt)2(4,4′-bipy)(4H2O)](NO3)4·4H2O (5), [Zn(tpt)(OAc)2]·5H2O (6) (terpy = 2,2′:6′,2′-terpyridine, tpt = 2,4,6-tri(2-pyridyl)-1,3,5-triazine, 4,4′-bipy = 4,4′-bipyridine) were synthesized and structurally characterized. The abundant hydrogen-bonding interactions extend complex 2 into ladder-like 1D chains, discrete molecules of 4 into a 2D layer structure, complex 5 into a 2D hydrogen-bonded network through linking the hydrogen-bonded ribbons with hexagonal and four-sided rings, and complex 6 into a 3D hydrogen-bonded network through combining water helical chains. Fluorescence analyses of 1–6 in the solid state are investigated at both room temperature and 10 K. The emission spectra of 1–2 show a large red shift, which is ascribed to ligand-to-ligand charge transfer combined with ligand-to-metal charge transfer, whereas emissions of 4–6 all originate from intraligand π-π* transitions. In organic solvents, 1–6 behave very differently and their emission spectra exhibit various luminescences, with an obvious blue shift indicating strong solvent effects. The X-ray diffraction and thermal gravimetric analyses for complexes 1–6 are also reported.