Two-dimensional viologen-based lanthanide coordination polymers as multi-stimuli responsive materials to light and amines with a fluorescence response.

Integrating multi-stimuli response properties in one molecule is challenging. This study presents two 2D polymers, [(Bpydp)Ln(HO)(BDC)]·NO·2HO (Ln = Eu(1), Tb(2)), exhibiting rapid photo-responsiveness and the ability to detect specific small-molecule amines. In particular, complex 1 combines the functions of inkless printing, amine detection, anti-counterfeiting, and fluorescence recognition.

Constructing high axiality mononuclear dysprosium molecular magnets a regulation-of-co-ligands strategy.

Two lanthanide complexes with formulae [Dy(L)(pentafluoro-PhO)] (1) and [Dy(L)(2,6-difluoro-PhO)](BPh) (2) (L = 2,14-dimethyl-3,6,10,13,19-pentaazabicyclo[13.3.1]nonadecal (19),2,13,15,17-pentaene) were structurally and magnetically characterized.

Two Three-Dimensional Ln Coordination Polymers Exhibiting Luminescent Sensing and a Magnetocaloric Effect.

Two lanthanide 3D coordination polymers [Ln(L)Cl(HO)] (Ln = Eu (), Gd ()) with quinoline-2-carboxylic acid (HL) as the ligand were successfully synthesized and characterized. Complex exhibits a highly sensitive and selective luminescent response to 2,6-dipicolinic acid (DPA) in tap water and is virtually unaffected by interferences such as amino acids, aromatic carboxylic acids, and ions. With the addition of DPA, the luminescence intensity of complex decreases rapidly to the naked eye.

Multifunctional lanthanide-based single-molecule magnets exhibiting luminescence thermometry and photochromic and ferroelectric properties.

Lanthanide-based single-molecule magnets (SMMs) have captivated the attention of researchers due to their great potential application in quantum information processing, storage, spintronics . Recent years have witnessed continuous breakthroughs in the field of SMMs, which make them very promising to be used in future practical functional applications. However, there remain formidable obstacles involving suppression of the quantum tunneling of magnetization (QTM) to maximize magnetic anisotropy, integrating and applying them in devices .

Integrating Asymmetric O-B-N Unit in Multi-Resonance Thermally Activated Delayed Fluorescence Emitters towards High-Performance Deep-Blue Organic Light-Emitting Diodes.

Developing deep-blue thermally activated delayed fluorescence (TADF) emitters with both high efficiency and color purity remains a formidable challenge. Here, we proposed a design strategy by integrating asymmetric oxygen-boron-nitrogen (O-B-N) multi-resonance (MR) unit into traditional N-B-N MR molecules to form a rigid and extended O-B-N-B-N MR π-skeleton. Three deep-blue MR-TADF emitters of OBN, NBN and ODBN featuring asymmetric O-B-N, symmetric N-B-N and extended O-B-N-B-N MR units were synthesized through the regioselective one-shot electrophilic C-H borylation at different positions of the same precursor.

One-Dimensional Chain Viologen-Based Lanthanide Multistimulus-Responsive Materials with Photochromism, Photoluminescence, Photomagnetism, and Ammonia/Amine Vapor Sensing.

In this work, a series of novel multistimulus-responsive lanthanide coordination polymers {[LnL(HO)]Cl·3HO} (Ln = Dy, Tb, Eu) constructed using a dicarboxylic acid viologen derivative L (L = ,'-4,4'-bipyridiniodipropionate) and LnCl·6HO were prepared. All materials showed positive responses to UV light, and the photochromic phenomena accompanied by significant photoquenching of photoluminescence could be observed through a photoelectron transfer mechanism. Strikingly, the Dy analogue displayed photomagnetic behavior, as well as responded positively to small molecules of inorganic ammonia/organic amines.

Schiff base tetranuclear ZnLn single-molecule magnets bridged by hydroxamic acid in association with near-infrared luminescence.

A series of Zn-Ln heteronuclear SMMs constructed by using a hexadentate compartment Schiff base Zn-precursor and lanthanoid ions were structurally and magnetically characterized, in which the two [Zn-Ln] moieties are bridged by a series of hydroxamic acids, resulting in double-decker tetranuclear complexes with the molecular formulae [ZnLLn(CHO)(qua)](CFSO)·2CHOH ((1) Ln = Dy; (7) Ln = Yb), [ZnLLn(CHO)(bnz)](CFSO)·2CHOH ((2) Ln = Dy), [ZnLLn(CHO)(aca)](CFSO)·2CHOH ((3) Ln = Dy; (8) Ln = Yb), [ZnLDy(CHO)(bnz)](CFSO)·2CHOH (4), [ZnLDy(CHO)(aca)](CFSO)·2CHOH (5), and [ZnLDy(CHO)(bnz)](CFSO)·2CHOH (6) (HL = ,'-bis(2-hydroxy-3-methoxybenzylidene)-1,2-phenylenediamine, HL = ,'-bis(2-hydroxy-3-methoxybenzylidene)-propane-1,2-diamine, HL = ,'-bis(3-methoxysalicylidene)-1,3-propanediamine, qua = 2-quinolinecarboxylic acid, bnz = benzhydroxamic acid and aca = acetohydroxamic acid). Strikingly, the slow magnetic relaxation can be tuned by modifying the steric hindrance and/or electronic effect on the backbone of the Shiff base and the terminal substituents of hydroxamic acid, as well the magneto-structural correlations are studied. Furthermore, Yb congeners 7 and 8 were synthesized to explore dual-functional materials with both magnetic and fluorescence properties, and they displayed both slow magnetic relaxation and near-infrared (NIR) properties; the low temperature NIR spectroscopic data were correlated with the corresponding slow magnetic relaxation mechanism involving thermally activated ground states to the excited state.

High local coordination symmetry around the spin center and the alignment between magnetic and symmetric axes together play a crucial role in single-molecule magnet performance.

A tetradentate 8-hydroxyquinoline-based acyl hydrazone ligand (HL1 = 8-hydroxyquinoline-2-carboxaldehyde-(aminourea)hydrochloride) was elaborately used to construct a mononuclear dysprosium complex DyCl3HL1·CH3OH (1) with a nearly ideal pentagonal bipyramid coordination geometry (D5h) surrounding the Dy(iii) ion to achieve the significant performance of single-molecule magnets (SMMs). Meanwhile, the isolated high local symmetry center was successfully kept intact and further bridged to a series of double bipyramid systems by two phenolic oxygen atoms of the acyl hydrazone ligands (HL1 and HL2 = 8-hydroxyquinoline-2-carboxaldehyde-(benzoyl)hydrazine), with the formulae [Dy2Cl4(L1)2(CH3OH)2]·4C5H5N (2) and [Dy2Cl4(L2)2]·2CH3CN (3). In addition, the monodentate co-ligand anion was replaced by a larger sterically hindered ligand and a bidentate monovalent β-diketonate anion to generate [Dy2(tfo)4(L2)2(EtOH)2] (4), [Dy2(tta)4(L2)2(EtOH)2]·2(EtOH) (5) and [Dy2(dbm)4(L2)2(EtOH)2] (6) (tfo = trifluoromethanesulfonic acid, dbm = dibenzoylmethane, tta = 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione) with eight-coordinate geometry.

From zero-dimensional to one-dimensional chain N-oxide bridged compounds with enhanced single-molecule magnetic performance.

A series of dinuclear dysprosium complexes bridged by pyridine-NO ligands with formula [Ln2(BTA)6(pyNO)2] (1Dy, Ln = Dy, 1Y, Ln = Y and 1Gd, Ln = Gd) (BTA = benzoyltrifluoroacetone, pyNO = pyridine-N-oxide) were structurally and magnetically characterized. The X-ray crystallographic analyses of the structures revealed that the NO group serves as the effective bridge to link two Dy(iii) centers and the periphery β-diketonate (BTA) ligands complete the rest of the coordination sphere. The dynamic magnetic measurements revealed that complex 1Dy displayed significant zero-field single-molecule magnetic (SMM) behaviour with 72 K energy barrier and 2.