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A new series of mononuclear copper(I) complexes 1 – 3 possessing functionalized 6-methoxycarbonyl-2,2′-bipyridine and phosphine mixed ligands have been synthesized and characterized. Each Cu(I) atom gives an N 2 P 2 distorted tetrahedral configuration, in which the dihedral angles between two pyridyl rings follow a ranking of 1 (4.640°) < 2 (av. 9.065°) < 3 (15.648°), while a reverse order lies in the dihedral angles between the methoxycarbonyl and its conjoined pyridyl ring ( 1 (15.224°) > 2 (av. 8.983°) > 3 (2.786°)). Complexes 1 – 3 show a weak low-energy absorption band at 330–500 nm in CH 2 Cl 2 solution, ascribed to charge-transfer transitions with appreciable 1 MLCT character, as supported by TD-DFT calculations. The solid-state luminescence is observed in 1 – 3 at room temperature, which is affected by the phosphine, the substituents on the 2,2′-bipyridyl, and the above-mentioned dihedral angles. [ABSTRACT FROM AUTHOR]

• Structural regulation of luminescent 0D organic copper(I) halides. • Tunable luminescence with phosphonium cation by varying the halogen components. • DFT calculations clarify emission mechanisms for advancing optical material design. Here we report three zero-dimensional (0-D) copper cluster structures, (2-TTPS)[CuCl 2 ] (1), (2-TTPS) 2 [Cu 4 Br 6 ] (2), and (2-TTPS) 4 [Cu 4 I 8 ] (3), formed by self-assembly of the 2-TTPSX ligand (2-TTPSX = triphenyl(thiophen-2-yl)phosphonium chloride/bromide/iodide) with neutral CuCl/CuBr/CuI, respectively. The CuX salts exhibit a propensity to form high nuclearity aggregates or clusters, leading to a specific structural richness. In 1 , two [CuCl 2 ]− units are staggered along the c-axis. In 2 , the larger [Cu 4 Br 6 ]2− inorganic unit is completely encapsulated by 2-TTPS+ cations, with each Cu+ located at the center of a [CuBr 4 ]3− tetrahedral structure. The copper cluster in 3 is characterized by an unprecedented, centrosymmetric tetramer formation. The variation in copper cluster types is achieved through the control of a single crystal growth technique using different CuX salts for assembly. This work introduces the synthetic methods, crystallographic features, and optical properties of the three materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Novel wide bandgap polymer donors (P03 and P07) with an acceptor 1 -π-acceptor 2 -π configuration are designed and synthesized. The best-performing P03-based polymer solar cell delivers an outstanding power conversion efficiency of 15.03% which is the highest among all copolymers with acceptor 1 -π-acceptor 2 -π-type molecular configurations. [Display omitted] • Polymer donors with an acceptor 1 -π-acceptor 2 -π configuration are developed. • The polymers show wide bandgaps with deep-lying HOMO energy levels. • The best polymer achieves an excellent power conversion efficiency of 15.03% To maximize the photovoltaic performance of polymer solar cells (PSCs), polymer donors and nonfullerene acceptors (NFAs) should be designed with complementarily optical and electronic properties as well as desirable morphological features. Currently, high-performance polymer donors are mainly constructed by alternating copolymerization of electron-rich (D) and electron-deficient (A) units. Here, we demonstrate that acceptor 1 -π-acceptor 2 -π (A 1 -π-A 2 -π)-type polymer donors constructed by copolymerization of two different A units can achieve comparable photovoltaic properties with those of D-π-A-π-type counterparts. By using the ladder-type 4,10-bis(2-hexyldecyl)-thieno[2ˊ,3ˊ:5,6]pyrido[3,4-g]thieno-[3,2-c]isoquinoline-5,11-dione as A 1 unit, difluorobenzotriazole or benzodithiophene-4,8-dione as A 2 unit, and thiophene unit as the π bridge, two A 1 -π-A 2 -π-type copolymers, P03 and P07, are successfully synthesized. Due to the weakened intramolecular charge-transfer effect, P03 and P07 exhibit wide bandgaps of 1.88 and 1.74 eV, respectively. In combination with the NFA of L8-BO, the P03:L8-BO-based blend shows superior crystallinity and uniform phase-separated morphology thereby leading to a higher power conversion efficiency (PCE) of 15.03 % in comparison with the P07:L8-BO-based blend which shows a PCE of 9.84 %. Notably, the 15.03 % efficiency is by far the highest value for PSCs based on A 1 -π-A 2 -π-type polymer donors. These results provide useful guidance for the future design of high-performance donor copolymers for PSCs. [ABSTRACT FROM AUTHOR]

As low‐dimensional lead‐free hybrids with higher stability and lower toxicity than those of three‐dimensional lead perovskites, organic antimony(III) halides show great application potential in opt‐electronic field owing to diverse topologies along with exceptional optical properties. We report herein an antimony(III) hybrid (MePPh3)2SbCl5 with a zero‐dimensional (0D) structure, which exhibits brilliant orange emission peaked at 593 nm with near‐unity photoluminescent quantum yield (99.4 %). The characterization of photophysical properties demonstrates that the broadband emission with a microsecond lifetime (3.24 μs) arises from self‐trapped emission (STE). Electrically driven organic light‐emitting diodes (OLEDs) based on neat and doped films of (MePPh3)2SbCl5 were fabricated. The doped devices show significant improvement in comparison to non‐doped OLEDs. Owing to the much improved surface morphology and balanced carrier transport in light‐emitting layers of doped devices, the peak luminance, current efficiency (CE) and external quantum efficiency (EQE) are boosted from 82 cd m−2 to 3500 cd m−2, 1.1 cd A−1 to 6.8 cd A−1, and 0.7 % to 3.1 % relative to non‐doped devices, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • The acceptor with auxochromic groups showed an increased absorption coefficient. • Alkylthio groups lead to the acceptor with an increased charge carrier mobility. • A high efficiency of 15.01% was achieved for the nonfullerene acceptor. Nonfullerene acceptors (NFAs) that efficiently harvest sunlight and transport the consequent charge are key to advancing the performance of polymer solar cells (PSCs). Herein we demonstrate that the NFA with alkylthio side-chains incorporated in the heteroheptacene core (MS1) shows a significantly increased molar extinction coefficient and enhanced molecular ordering in comparison with the counterpart with alkyl side-chains (MC1). Therefore, in combination with a benchmark donor polymer (PM6), the resulting MS1-based PSC shows an enhanced power conversion efficiency (PCE) of 14.13% with a fill factor (FF) of 71.66% and a short-circuit current density (J sc) of 21.70 mA cm−2 comparing with the MC1-based PSC which shows a PCE of 11.87% with a FF of 62.55% and a J sc of 20.39 mA cm−2. The enhanced photovoltaic performance for the MS1-based PSC can be in part attributed to the increased light-harvesting ability of the MS1-based active layer and in part attributed to its boosted carrier mobilities and reduced charge recombination. Moreover, with an electrode optimization, the best-performing MS1-based PSC shows a further enhanced PCE of 15.01% which is an impressive efficiency among all acceptor–donor–acceptor type NFAs reported to date. This work suggests the important role of the auxochromic groups in the electron-rich core in determining the photovoltaic performance of NFAs. [ABSTRACT FROM AUTHOR]

Conventional fluorescent materials frequently exhibit narrow-band emissions with a small full width at half-maximum (fwhm) due to localized-state characteristics, but electroluminescence is less efficient owing to the utilization of only singlet excitons. In this work, taking advantage of naphthalimide (NAI)-acetylide derivatives with a rigid planar structure and localized transition characteristics, we elaborately designed two mononuclear Pt(II) complexes with weak double emissions of fluorescence and phosphorescence. Taking them as synthetic precursors, we prepared three PtAu 2 heteronuclear clusters and successfully attained highly efficient narrow-band red phosphorescence with the fwhm below 30 nm. Both theoretical and experimental results suggest that the phosphorescence of PtAu 2 clusters mainly originates from the naphthalimide-localized 3 IL (intraligand) triplet state. Solution-processed organic light-emitting diodes (OLEDs) achieved highly efficient narrow-band red electroluminescence with an external quantum efficiency (EQE) of 16.7%. The CIE coordinates of the electroluminescence (0.69, 0.31) closely match the standard red emission for ultrahigh-definition display.

Chiral 3D perovskites pose challenges compared to lower-dimensional variants due to limited chiral organic cation options. Here, we present a universal and controlled method for synthesizing chiral 3D lead halide perovskites using organic amines or alcohols as chiral templates. Introducing these templates to PbCl 2 in N , N -dimethylformamide (DMF) under acidic conditions induces the crystallization of R/S [DMA]PbCl 3 (DMA = dimethylamine). The resulting structure aligns with the templates used, stemming from the helical Pb 2 Cl 9 5- chain as verified by single-crystal X-ray diffraction. Furthermore, the chiral perovskite exhibits absorption and circular dichroism (CD) signals in the high-energy band, enabling the circularly polarized light (CPL) detection in the UV spectrum. A CPL detector constructed by this chiral perovskite demonstrates excellent performance, boasting an anisotropy factor for photocurrent ( g Iph ) of 0.296. Our work not only introduces a novel and controllable method for crafting chiral perovskites but also opens new avenues for circularly polarized light detection.

Six amides, including a new N -alkylamide ( 1 ), four known N -alkylamides ( 2 - 5 ) and one nicotinamide ( 6 ) were isolated from Litsea cubeba (Lour.) Pers., which is a pioneer herb traditionally utilized in medicine. Their structures were elucidated on the basis of 1D and 2D NMR experiments and by comparison of their spectroscopic and physical data with the literature values. Cubebamide ( 1 ) is a new cinnamoyltyraminealkylamide and possessed obvious anti-inflammatory activity against NO production with IC 50 values of 18.45 μM. Further in-depth pharmacophore-based virtual screening and molecular docking were carried out to reveal the binding mode of the active compound inside the 5-LOX enzyme. The results indicate that L. cubeba , and the isolated amides might be useful in the development of lead compounds for the prevention of inflammatory diseases.

An asymmetric structure is an important strategy for designing highly conductive molecular wires for a gap-fixed molecular circuit. As the conductance enhancement in the current strategy is still limited to about 2 times, we inserted a methylene group as a spacer in a conjugated structure to modulate the structural symmetry. We found that the conductance drastically enhanced in the asymmetric molecular wire to 1.5 orders of magnitude as high as that in the symmetric molecular wire. First-principles quantum transport studies attributed the effective enhancement to the synchronization of improved energy alignment and nearly symmetric coupling between the frontier orbitals and the electrodes.

Diradicaloids are generally high-energy molecules with open-shell configuration and are quite reactive. In this work, we report a feasible synthetic approach to attaining exceptionally stable copper(I) metallacyclopentadiene diradicaloids through ligand engineering. Copper(I)-hybrid cyclopentadiene diradicaloids 1c - 6c that absorb intensely in visible regions were successfully prepared in stoichiometrical yields under UV light irradiation. The diradicaloids originate from the C-C bonding coupling of two side-by-side-arranged ethynyl groups in complexes 1 - 6 upon photocyclization. By rational selection of substituents in triphosphine ligands, we systematically modulate the kinetic behavior of diradicaloids 1c - 6c in the thermal decoloration process. With precise ligand design, we are able to obtain exceptionally stable copper(I)-hybrid cyclopentadiene diradicaloids with a half-life as long as ca. 40 h in CH 2 Cl 2 solution at ambient temperature. As demonstrated by electron paramagnetic resonance (EPR) and variable-temperature magnetic studies, the diradicaloids manifest a singlet ground state, but they are readily populated to a triplet excited state through thermal activation in view of a small singlet-triplet energy gap of -0.39 kcal mol -1 . The diradicaloids show two-step quasi-reversible reduction waves at about -0.5 and -1.0 V ascribed to successive one-electron-accepting processes, coinciding perfectly with the characteristics of diradicals.

An accurate rule for predicting conductance is the cornerstone of developing molecular circuits and provides a promising solution for miniaturizing electric circuits. The successful prediction of series molecular circuits has proven the possibility of establishing a rule for molecular circuits under quantum mechanics. However, the quantitatively accurate prediction has not been validated by experiments for parallel molecular circuits. Here we used 1,3-dihydrobenzothiophene (DBT) to build the parallel molecular circuits. The theoretical simulation and single-molecule conductance measurements demonstrated that the conductance of the molecule containing one DBT is the unprecedented linear combination of the conductance of the two individual channels with respective contribution weights of 0.37 and 0.63. With these weights, the conductance of the molecule containing two DBTs is predicted as 1.81 nS, matching perfectly with the measured conductance (1.82 nS). This feature offers a potential rule for quantitatively predicting the conductance of parallel molecular circuits.

Reaction of [Au(tht) 2 ](ClO 4 ) (tht = tetrahydrothiophene), [Cu(CH 3 CN) 4 ](ClO 4 ), 3,6-di- tert -butyl-1,8-diethynyl-9 H -carbazole (H 3 decz), and bis(2-diphenylphosphinophenyl)ether (POP) in the presence of triethylamine (NEt 3 ) gave the cluster complex Au 4 Cu 2 (decz) 2 (POP) 2 as yellow crystals. As revealed by X-ray crystallography, the Au 4 Cu 2 cluster exhibits scissor-like structure sustained by two decz and two POP ligands and stabilized by Au-Cu and Au-Au interactions. The Au 4 Cu 2 cluster shows bright yellow to orange photoluminescence upon irradiation at >300 nm, arising from 3 [π (decz)→5d (Au)] 3 LMCT (ligand-to-metal charge transfer) and 3 [π→π* (decz)] 3 IL (intraligand) triplet states as revealed by theoretical and computational studies. When it is mechanically ground, reversible phosphorescence conversion from yellow to red is observed owing to more compact molecular packing and thus stronger intermetallic interaction. Variable-temperature luminescence studies reveal that it displays distinct red-shifts of the emission whether the temperature is elevated or lowered from ambient temperature, suggestive of exceptional thermochromic phosphorescence characteristics.

Two asymmetric PtAu 2 complexes having HC≡CC 6 H 4 C≡CH (1,4-diethynylbenzene) or HC≡CCarbC≡CH (2,7-diethynyl-9-(2,3,5,6-tetrafluorophenyl)-9H-carbazole) and the corresponding bis(acetylide)-linked Pt 2 Au 4 complexes are prepared and characterized. The structures of PtAu 2 complexes 1 and 3 together with Pt 2 Au 4 complex 2 are determined by X-ray crystallography. Relative to PtAu 2 complexes, bis(acetylide)-linked Pt 2 Au 4 complexes not only display a distinct red shift of the emission but also provide a much higher phosphorescent efficiency. Utilizing highly emissive Pt 2 Au 4 complexes as phosphorescent dopants, high-efficiency solution-processed OLEDs are obtained with peak current efficiency of 75.9 cd A -1 and external quantum efficiency of 19.0% at luminance of 336 cd m -2 and voltage of 5.2 V. When two PtAu 2 moieties are linked by a bis(acetylide) ligand, the corresponding Pt 2 Au 4 complexes show a much improved electroluminescent performance compared with that of asymmetric PtAu 2 complexes.

Two heteroctanuclear Au 4 Ag 4 cluster complexes of 4,5-diethynylacridin-9-one (H 2 L) were prepared through the self-assembly reactions of [Au(tht) 2 ](CF 3 SO 3 ), Ag(tht)(CF 3 SO 3 ), H 2 L and PPh 3 or PPh 2 Py (2-(diphenylphosphino)pyridine). The Au 4 Ag 4 cluster consists of a [Au 4 L 4 ] 4- and four [Ag(PPh 3 )] + or [Ag(PPh 2 Py)] + units with Au 4 L 4 framework exhibiting a twisted paper clip structure. In CH 2 Cl 2 solutions at ambient temperature, both compounds show ligand fluorescence at ca. 463 nm as well as phosphorescence at 650 nm for 1 and 630 nm for 2 resulting from admixture of 3 IL (intraligand) of L ligand, 3 LMCT (from L ligand to Au 4 Ag 4 ) and 3 MC (metal-cluster) triplet states. Crystals or crystalline powders manifest bright yellow-green phosphorescence with vibronic-structured emission bands at 530 (568sh) nm for complex 1 and 536 (576sh) nm for complex 2 . Upon mechanical grinding, yellow-green emission in the crystalline state is dramatically converted to red luminescence centered at ca. 610 nm with a drastic redshift of the emission after crystal packing is destroyed.

An in-depth study on a stimuli-responsive tetranuclear cuprous luminescent complex is reported and gives new insights into the origin and possible use of the observed stimuli-responsive luminescence. Its crystalline polymorphs with two different shapes are obtained by using different crystallization solvents and show distinct emissions, with one being blue emissive and the other being yellow emissive. Upon grinding, only the blue-emitting polymorph has a marked change in the emission color from blue to yellow, and its ground sample exhibits a yellow emission similar to that of the yellow-emitting polymorph. Interestingly, the yellow-emitting polymorph after exposure to acetone vapor can emit a blue emission and display luminescence mechanochromism similar to that of the blue-emitting polymorph. Single-crystal structural analyses of the two different polymorphs reveal the relationship between the mechanochromic luminescence and the geometrical configuration of the {Cu(μ-dppm) 2 Cu} unit and intramolecular "pyridyl/phenyl" π···π interactions, supported as well by their PXRD, FT-IR, TGA, and PL studies in various states and by TD-DFT analyses. The results demonstrate the different roles of switchable intramolecular π···π interactions and the geometrical configuration of the {Cu(μ-dppm) 2 Cu} unit in this stimuli-responsive luminescence and potential applications of such stimuli-responsive luminescence in optical sensing and anticounterfeiting encryption technologies and deepen the understanding of such stimuli-responsive luminescence originating from switchable intramolecular π···π interactions. In addition, it is clearly suggested that the rational utilization of switchable intramolecular π···π interactions is a feasible route for developing stimuli-responsive intelligent luminescent materials and devices.

Unveiling the internal dynamics of rotation in molecular machine at single-molecule scale is still a challenge. In this work, three crank-shaped molecules are elaborately designed with the conformational flipping between syn and anti fulfilled by two naphthyl groups rotating freely along 1,3-butadiynyl axis. By investigating the single-molecule conductance using scanning tunnelling microscope break junction (STM-BJ) technique and theoretical simulation, the internal rotation of these crank-shaped molecules is well identified through low and high conductance corresponding to syn- and anti-conformations. As demonstrated by theoretically computational study, the orbital energy changes with the conformational flipping and influences the intraorbital quantum interference, thus eventually modulating the single-molecule conductance. This work demonstrates single-molecule conductance measurement to be a rational approach for characterizing the internal rotation of molecular machines.

Nonfullerene acceptors (MQ3, MQ5, MQ6) are synthesized using asymmetric and symmetric ladder-type heteroheptacene cores with selenophene heterocycles. Although MQ3 and MQ5 are constructed with the same number of selenophene heterocycles, the heteroheptacene core of MQ5 is end-capped with selenophene rings while that of MQ3 is flanked with thiophene rings. With the enhanced noncovalent interaction of O⋅⋅⋅Se compared to that of O⋅⋅⋅S, MQ5 shows a bathochromically shifted absorption band and greatly improved carrier transport, leading to a higher power conversion efficiency (PCE) of 15.64 % compared to MQ3, which shows a PCE of 13.51 %. Based on the asymmetric heteroheptacene core, MQ6 shows an improved carrier transport induced by the reduced π-π stacking distance, related with the increased dipole moment in comparison with the nonfullerene acceptors based on symmetric cores. MQ6 exhibits a PCE of 16.39 % with a V OC of 0.88 V, a FF of 75.66 %, and a J SC of 24.62 mA cm -2 ., (© 2021 Wiley-VCH GmbH.)

Highly soluble d 8 -d 10 heteronuclear phosphors afford an alternative approach to achieve high-efficiency organic light-emitting diodes (OLEDs) through a solution process. In this work, four highly phosphorescent d 8 -d 10 heteronuclear complexes with significant Pt-Au interactions were prepared. By judicious selection of sterically hindered and π-conjugated substituents in triphosphine ligands, the phosphorescence is dramatically promoted through effectively prohibiting nonradiative thermal relaxation with an efficiency of 0.94-0.99 in doping films. Exploiting highly emissive Pt-Au complexes as phosphorescent dopants, ultrahigh-efficiency solution-processed OLEDs were attained. The peak current efficiency, power efficiency, and external quantum efficiency are 96.2 cd A -1 , 65.0 lm W -1 , and 26.4% for the green-emitting PtAu 2 phosphor and 68.6 cd A -1 , 42.5 lm W -1 , and 25.1% for the orange-emitting Pt 2 Au phosphor, which represent the state-of-art for solution-processed OLEDs based on non-iridium phosphors.

In this work, rational design of highly soluble and phosphorescent Ag-Au cluster complexes with exceptional [2]catenane structures is conducted using 1,8-diethynyl-9 H -carbazole (H 3 decz) as a rigid U-shaped ligand with a distinguished hole-transport character. The self-assembly reaction of H 3 decz, Au + , and Ag + generated phosphorescent Ag 4 Au 6 cluster 1 (Φ em = 0.22 in CH 2 Cl 2 ) with H 2 decz - having a free ethynyl (-C≡CH) group. When the four free C≡CH groups in the Ag 4 Au 6 complex 1 are further bound to four (PPh 3 )Au + and four (PPh 3 )Ag + moieties through M-acetylide linkages, the formation of Ag 8 Au 10 cluster 2 not only eliminates nonradiative ethynyl C-H vibrational deactivation process but also improves dramatically the molecular rigidity so that the phosphorescent efficiency of the Ag 8 Au 10 cluster 2 (Φ em = 0.63) is nearly 3 times that of the Ag 4 Au 6 cluster 1 . The Ag 8 Au 10 cluster structure is further rigidified using diphsophine Ph 2 P(CH 2 ) 4 PPh 2 (dppb) in place of PPh 3 so that the phosphorescence of the Ag 8 Au 10 cluster 3 (Φ em = 0.77) is more efficient than that of 2 . Making use of the Ag 8 Au 10 clusters as phosphorescent dopants, high-efficiency solution-processed organic light-emitting diodes (OLEDs) were achieved with current efficiency (CE) and external quantum efficiency (EQE) of 47.2 cd A -1 and 15.7% for complex 2 and 50.5 cd A -1 and 14.9% for complex 3 .

The reaction of 3,6-di tert -butyl-1,8-bis(diphenylphosphino)-9-methyl-9H-carbazole (L) with CuBr resulted in the isolation of tetranuclear copper(I) complex Cu 4 Br 4 L 2 as two colorless crystal morphs, i.e., green-emitting 1G and yellow-emitting 1Y . As demonstrated by X-ray crystallography, the Cu 4 Br 4 moiety in both 1G and 1Y adopts the same chair conformations. When L is bonded perpendicularly to the Cu 4 plane, 1G with green emission is obtained, while it gives a yellow emission of 1Y once the L is parallelly bonded to Cu 4 plane. Theoretical computational studies suggest that the variation in ligand orientation results in a different degree of structural distortion in triplet state and thus different luminescent energy. Particularly, 1Y undergoes dramatic structural distortion from the ground (S 0 ) to triplet excied state (T 1 ). Interestingly, 1G can be converted into 1Y upon exposed to saturated hexane vapor, which would return to 1G upon exposure to acetonitrile vapor. As demonstrated experimentally and theoretically, the reversible luminescence transformation between 1G and 1Y is ascribed to the variation of ligand L orientations.

Mechanochromic luminescence materials have attracted rapidly growing interest. Nevertheless, the designed synthesis of such materials remains a challenge, and there have been few examples based on weak intramolecular interactions. Herein, we report a new approach for preparing mechanochromic luminescence materials of Cu(I) complexes, i.e., constructing a photoluminescence system that bears a large coplanar multinuclear Cu(I) unit showing weak intramolecular π···π interactions with the planar rings of the coordinated ligands in the molecule. Using it, a series of novel mechanochromic luminescent tetranuclear Cu(I) complexes have been successfully designed and synthesized. As revealed by single-crystal X-ray crystallography, these Cu(I) complexes share an identical {Cu 4 [μ 3 -η 2 (N,N),η 1 (N),η 1 (N)-pyridyltetrazole] 2 } 2+ planar fragment whose coplanar pyridyl rings exhibit weak intramolecular π···π interactions with the phenyl rings of the coordinated phosphine ligands in the molecule. All of these Cu(I) complexes exhibit reversible mechanochromic luminescence, which can be attributed to the change in the rigidity of the molecular structure resulting from the disruption and restoration of intramolecular π···π interactions between the pyridyl and phenyl rings triggered by grinding and CH 2 Cl 2 vapor, as supported by powder X-ray diffraction and Fourier transform infrared spectrometry. In addition, the results might provide a new route for developing mechanochromic luminescence materials of Cu(I) complexes for intelligent responsive luminescent devices.

Background: Gastrointestinal (GI) dysfunction is a common and important complication of acute pancreatitis (AP), especially in patients with severe AP. Despite this, there is no consensus means of obtaining a precise assessment of GI function., Aim: To determine the association between acute gastrointestinal injury (AGI) grade and clinical outcomes in critically ill patients with AP., Methods: Patients with AP admitted to our pancreatic intensive care unit from May 2017 to May 2019 were enrolled. GI function was assessed according to the AGI grade proposed by the European Society of Intensive Care Medicine in 2012, which is mainly based on GI symptoms, intra-abdominal pressure, and feeding intolerance in the first week of admission to the intensive care unit. Multivariate logistic regression analysis was performed to assess the association between AGI grade and clinical outcomes in critically ill patients with AP., Results: Among the 286 patients included, the distribution of patients with various AGI grades was 34.62% with grade I, 22.03% with grade II, 32.52% with grade III, and 10.84% with grade IV. The distribution of mortality was 0% among those with grade I, 6.35% among those with grade II, 30.11% among those with grade III, and 61.29% among those with grade IV, and AGI grade was positively correlated with mortality ( χ 2 = 31.511, P < 0.0001). Multivariate logistic regression analysis showed that age, serum calcium level, AGI grade, persistent renal failure, and persistent circulatory failure were independently associated with mortality. Compared with the Acute Physiology and Chronic Health Evaluation II score (area under the curve: 0.739 vs 0.854; P < 0.05) and Ranson score (area under the curve: 0.72 vs 0.854; P < 0.01), the AGI grade was more useful for predicting mortality., Conclusion: AGI grade is useful for identifying the severity of GI dysfunction and can be used as a predictor of mortality in critically ill patients with AP., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflict of interest., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)

Bis(diphenylphosphinomethyl)phenylphosphine (dpmp)-supported Pt 2 Au heterotrinuclear complexes [Pt 2 Au(dpmp) 2 (C≡CPh) 4 ](ClO 4 ) ( 1 ), [Pt 2 Au(dpmp) 2 (DEBf)(C≡CPh) 2 ](ClO 4 ) ( 2 ), and [Pt 2 Au(dpmp) 2 (DECz)(C≡CPh) 2 ](ClO 4 ) ( 3 ) were prepared and used in organic light-emitting diodes (OLEDs) as a new class of light emitters, where DEBf = dibenzofuran-4,6-diacetylide and DECz = 3,6-di- tert -butylcarbazole-1,8-diacetylide. Although the flexible structure of Pt 2 Au complex 1 (λ em = 503 nm, Φ em < 0.1%) results in weak photoluminescence in fluid CH 2 Cl 2 , complexes 2 (λ em = 585 nm, Φ em = 4.9%) and 3 (λ em = 589 nm, Φ em = 3.2%) with a rigid conformation give a much stronger phosphorescence. The displacement of two σ-bonded phenylacetylide ligands with a diacetylide ligand such as DEBf and DECz to fasten Pt 2 Au structures facilitates greatly luminescent emission so that the emissive quantum yield in doping film is as high as 89% for 2 and 93% for 3 . As revealed by a theoretical study, the severe structural distortion of diacetylide-linked Pt 2 Au complexes 2 (λ em = 585 nm) and 3 (λ em = 589 nm) in a triplet excited state gives rise to significant red shifts of phosphorescent emission spectra relative to that of complex 1 (λ em = 503 nm). By means of Pt 2 Au complexes as phosphorescent emitters, solution-processed OLEDs achieved a relatively low external quantum efficiency (EQE < 9.5%) when commercial poly(ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) was used as the hole-injection layer (HIL). In contrast, the peak EQE was increased to 18.3% with a dramatic increase of efficiency by the use of modified HILs composed of PEDOT:PSS and PSS-Na, which provide a higher work function and a better film morphology.

A new sublimable dicopper(I) complex bearing 1,2-bis(diphenylphosphino)ethane and 5-trifluoromethyl-3-(2'-pyridyl)pyrazolate ligands has been designed and synthesized, and its crystalline solvated and nonsolvated compounds have also been obtained and investigated. It is shown that only the crystalline solvated compound exhibits reversible and selective luminescence vapochromism, arising from its unique "pyridyl/CH 2 Cl 2 /pyridyl" organic sandwich-like stacking arrangement revealed by X-ray crystallography, as supported by time-dependent density functional theory calculations. Additionally, the neutral Cu(I) complex has excellent thermal stability and sublimability, good solid-state luminescence properties, and TADF character, and it is suggested to be a good emitter for vapor-deposited organic light-emitting diodes.

Three quinoline-based zinc(ii)-Schiff base complexes were synthesized and characterized by X-ray crystallography. They exhibit remarkable aggregation-induced emission enhancement (AIEE) in acetonitrile/diethyl ether mixtures due to the conversion of weak luminescence in homogeneous solution into strong emission in the nano-aggregated phase after increasing the fractions of diethyl ether. Interestingly, the AIEE performance can be significantly promoted by joining the two quinoline units through an alkoxy chain. Moreover, they show reversible mechanochromic luminescence behavior between dark and bright states during the grinding-fuming cycles, due to the modulation of morphologies between amorphous and crystalline states. Introducing an electron donating group in the para-position of aniline significantly improves the mechanochromic luminescence effect with a more accessible and distinct emission colour contrast. The molecular packing in the crystalline phase and time-dependent density functional theory (TD-DFT) calculations demonstrate that multiple intermolecular C-Hπ and π-π interactions significantly strengthen the molecular rigidity and enhance the intramolecular charge-transfer (ICT) characteristics, leading to the effective emission enhancement in crystalline/nano-aggregated states. The novel AIEE and reversible mechanochromic luminescence properties point to the promising potential applications of these complexes in smart fluorescent materials.

A feasible synthetic approach to achieve Ag8, Ag16 and Ag29 silver(i) nanoclusters is reported by the use of 1,8-diethynyl-9H-carbazole (H3decz) as a directing ligand. The silver(i) nanoclusters exhibit room-temperature photoluminescence in both solution and solid state. The emission band shows stepwise red-shifts from visible to near-infrared region with the increase of cluster nuclearity following 2 (Ag8, λem = 571 nm) → 3 (Ag16, λem = 651 nm) → 4 (Ag29, λem = 916 and 875sh nm) in fluid CH2Cl2.

Dinuclear Cu(I) complexes bearing hexadentate, macrocyclic N-heterocyclic carbene (NHC) ligands, [Cu 2 (L 1 )(CH 3 CN)][PF 6 ] 2 (1) and [Cu 2 (L 2 )(CH 3 CN)] 2 [Cu 2 (L 2 )(CH 3 CN) 2 ][PF 6 ] 6 (2), have been synthesized by the reactions of [H 4 L][PF 6 ] 4 (L = L 1 , L 2 ) with excess Cu 2 O in acetonitrile. Crystallizations of the heat-treated samples of 1 and 2 from acetone/methanol/ether or CH 3 NO 2 /ether result in [Cu 2 (L 1 )][PF 6 ] 2 (3) and [Cu 2 (L 2 )][PF 6 ] 2 (4). Complexes 1-4 are emissive with luminescent maxima at 464, 472, 540, and 488 nm in the solid state, respectively. The origin of the red shift of the emission maximum of 3 relative to the other three complexes has been studied by theoretical calculations, showing the cuprophilic interactions in the excited state of 3. The mechanochromic luminescent properties of 1-4 have been studied. After grinding in a mortar, a significant emission color change is found with a red shift of 98 nm for 1, 82 nm for 2, 20 nm for 3, and 64 nm for 4, respectively. These mechanochromic transformations are found to be a crystalline-to-amorphous conversion, which can be reverted by adding drops of the organic solvent or recrystallization. The possible correlations between the luminescent properties and structural modifications such as Cu···Cu distances are discussed.

A new sulfonylcalix[4]arene-based dinuclear terbium molecular container (1) was conveniently synthesized and utilized as a fluorescence probe for the detection of a well-known biomarker 1-hydroxypyrene (1-OHP), which is used for the evaluation of polycyclic aromatic hydrocarbons (PAHs). The sulfonylcalix[4]arene ligand could not only serve as an efficient antenna ligand to promote the ligand-to-metal energy transfer but also provide a suitable cavity to accommodate 1-OHP. Promising fluorescence quenching effects were well established during the titration of the compound 1 with 1-OHP, and these effects were due to the enhancement in the host-guest intermolecular charge transfer and the decrease in the ligand-to-metal energy transfer after the formation of the stable host-guest complex. The fluorescence sensing mechanism was clearly understood through the titration experiments, and the data could be fit with the Benesi-Hildebrand and Stern-Volmer models. The TbIII-TBSC-based luminescent sensor exhibited quick response, high sensitivity, and specific selectivity to 1-OHP, even in the presence of other constituents in urine, thus providing a new sensing platform for the clinical diagnosis of human exposure to PAHs.

A series of Ag(i) and Cu(i) complexes [Ag3(L1)2][PF6]3 (8), [Ag3(L2)2][PF6]3 (9), [Cu(L1)][PF6] (10) and [Cu(L2)][PF6] (11) have been synthesized by reactions of the tridentate amine-bis(N-heterocyclic carbene) ligand precursors [H2L1][PF6]2 (6) and [H2L2][PF6]2 (7) with Ag2O and Cu2O, respectively. Complexes 10 and 11 can also be obtained by transmetalation of 8 and 9, respectively, with 3.0 equiv. of CuCl. A heterometallic Cu/Ag-NHC complex [Cu2Ag(L1)2(CH3CN)2][PF6]3 (12) is formed by the reaction of 8 with 2.0 equiv. of CuCl. All complexes have been characterized by NMR, electrospray ionization mass spectrometry (ESI-MS), and single-crystal X-ray diffraction studies. The luminescence properties of 10-12 in solution and the solid state have been studied. At room temperature, 10-12 exhibit evident luminescence in solution and the solid state. The emission wavelengths are found to be identical at 483 nm in CH3CN, but they are 484, 480 and 592 nm in the solid state for 10-12, respectively. These results suggest that 12 dissociates into two molecules of 10 and Ag(i) ions in solution. Complex 12 is the first luminescent heterometallic Cu/Ag-NHC complex.

An asymmetric bis(dithienylethene-acetylide) ruthenium(II) complex trans-Ru(dppe) 2 (L1o)(L2o) (1oo) incorporating two different dithienylethene-acetylides (L1o and L2o) was designed to modulate multistate photochromism in view of the well separated ring-closing absorption bands between L1o and L2o. Upon irradiation with appropriate wavelengths of light, complex 1 undergoes stepwise photocyclization and selective photocycloreversion to afford four states (1oo, 1co, 1oc, and 1cc). As a contrast, symmetric complexes trans-Ru(dppe) 2 (L1o) 2 (2oo) and trans-Ru(dppe) 2 (L2o) 2 (3oo) with two identical dithienylethene-acetylides were synthesized, and the corresponding photochromic behavior was investigated. The photochromic properties of the oxidized species (1oo + /1co + /1oc + /1cc + , 2oo + /2co + /2cc + , and 3oo + /3co + /3cc + ) were also investigated. The ring-closing absorption bands of one-electron oxidized species 1oo + , 2oo + , and 3oo + show obvious blue shifts relative to those of 1oo, 2oo, and 3oo, respectively. The ring-closing absorption bands in both neutral and oxidized species grow progressively following oo → oc/co → cc and oo + → oc + /co + → cc + . As revealed by spectroscopic, electrochemical, and computational studies, complex 1 displays eight switchable states through stepwise photocyclization, selective cycloreversion, and a reversible redox process.

A new series of bimetallic Cu(I) complexes 1-5 triply bridged by a monoanionic or charge-neutral functionalized 3-(2'-pyridyl)-1,2,4-triazole in a μ-η 1 (N),η 2 (N,N) tridentate binding mode and two bis(diphenylphosphino)methane (dppm) ligands have been synthesized. Complexes 1-5 are singly or doubly charged dinuclear Cu(I) species with an eight-membered Cu 2 C 2 P 4 ring of {Cu(μ-dppm) 2 Cu} unit, in which 3 and 4 adopt the boat-boat conformation, while 1, 2, and 5 display the chair-boat form. In these dimeric copper(I) complex cations, one of the two Cu(I) ions is four-coordinated, in a highly distorted N 2 P 2 tetrahedral environment and the other is three-coordinated, in a distorted NP 2 trigonal planar arrangement. All these Cu(I) complexes exhibit a comparatively weak low-energy absorption in CH 2 Cl 2 solution, ascribed to the charge-transfer transitions with appreciable 1 MLCT contribution, as suggested by time-dependent density functional theory (TDDFT) analyses. Complexes 1-5 display good emission properties in both solution and solid states at ambient temperature, which are well-modulated via structural modification of 3-(2'-pyridyl)-1,2,4-triazole, including the alteration of the substituent type (-CF 3 , -H, -CH 3 , and -C(CH 3 ) 3 ) and position (ortho-, meta-, and para-position). Furthermore, the variation of the substituent (-CF 3 and -C(CH 3 ) 3 ) on the 5-site of the 1,2,4-triazolyl ring markedly influences the proton activity of the 1,2,4-triazolyl-NH, thus leading to the formation of both singly and doubly charged bimetallic Cu(I) species regulated by the NH ↔ N - conversion, resulting from NH deprotonation of the 1,2,4-triazolyl ring.

1,2-Bis[[(diphenylphosphino)methyl](phenyl)phosphino]ethane (dpmppe) was prepared as a new tetraphosphine, and the corresponding rac and meso stereoisomers were successfully separated in view of their solubility difference in acetone. The substitution of PPh 3 into Pt(PPh 3 ) 2 (C≡CR) 2 (R = aryl) with rac- or meso-dpmppe gives Pt(rac-dpmppe)(C≡CR) 2 or Pt(meso-dpmppe)(C≡CR) 2 , respectively. Using Pt(rac-dpmppe)(C≡CR) 2 or Pt(meso-dpmppe)(C≡CR) 2 as a precursor, PtAg 2 heterotrinuclear cluster complexes were synthesized and characterized by X-ray crystallography. Depending on the conformations of tetraphosphine, the structures of PtAg 2 complexes supported with rac- and meso-dpmppe are quite different. The higher molecular rigidity of rac-dpmppe-supported PtAg 2 complexes results in stronger phosphorescent emission than that of PtAg 2 species with meso-dpmppe. The high phosphorescent quantum yields (as high as 90.5%) in doping films warrant these PtAg 2 complexes as excellent phosphorescent dopants in organic light-emitting diodes (OLEDs). The peak current and external quantum efficiencies in solution-processed OLEDs are 61.0 cd A -1 and 18.1%, respectively. Electroluminescence was elaborately modulated by modifying the substituent in aromatic acetylide and the conformations in tetraphosphine so as to achieve cyan, green, green-yellow, yellow, and orange-red emission.

The process of molecular recognition is the assembly of two or more molecules through weak interactions. Information in the process of molecular recognition can be transmitted to us via physical signals, which may find applications in sensing and switching. The conventional signals are mainly limited to light signal. Here, we describe the recognition of diols with Cu(1,10-phenlothroline) 2 SeO 4 and the transduction of discrete recognition events into dielectric and/or ferroelectric signals. We observe that systems of Cu(1,10-phenlothroline) 2 SeO 4 ·(diol) exhibit significant dielectric and/or ferroelectric dependence on different diol molecules. The compounds including ethane-1,2-diol or propane-1,2-diol just show small temperature-dependent dielectric anomalies and no reversible polarization, while the compound including ethane-1,3-diol shows giant temperature-dependent dielectric anomalies as well as ferroelectric reversible spontaneous polarization. This finding shows that dielectricity and/or ferroelectricity has the potential to be used for signalling molecular recognition.

Cationic PtAu 2 heterotrinuclear complexes [PtAu 2 (dpmp) 2 (C[triple bond, length as m-dash]CR) 2 ] 2+ (dpmp = bis(diphenylphosphinomethyl)phenylphosphine, R = aryl) of aromatic acetylides were prepared. The PtAu 2 structures are supported through doubly bridging dpmp and stabilized by a significant Pt-Au interaction. They are highly phosphorescent in fluid CH 2 Cl 2 solution (Φ em = 23.5%-78.9%), the solid state (Φ em = 15.4%-70.2%), the PMMA film (Φ em = 39.9%-71.7%) and the doping film of 61% TCTA : 31% OXD-7 : 8% PtAu 2 complex (Φ em = 16.9%-67.9%). The phosphorescence arises mainly from 3 [π (C[triple bond, length as m-dash]CR) → π* (dpmp)] 3 LLCT and 3 [π (C[triple bond, length as m-dash]CR) → s/p (PtAu 2 )] 3 LMCT triplet excited states for carbazole-acetylide complexes, whereas other complexes display a 3 LLCT character mixed with noticeable PtAu 2 centered 3 [d → s/p] parentage. Utilizing a mixed host composed of hole-transporting TCTA and electron-transporting OXD-7 doped with 8% PtAu 2 species as a light-emitting layer and CuSCN as a hole-transporting layer through an orthogonal solution process, the devices exhibit highly efficient electrophosphorescence with the highest current efficiency (CE max ) of 51.7 cd A -1 and external quantum efficiency (EQE max ) of 14.5%. The efficiency roll-off is small in the practical brightness range of 500-5000 cd m -2 . The PtAu 2 complexes with carbazole-acetylides display a higher electroluminescence efficiency ascribed to their better hole-transporting character as well as more facile energy transfer from mixed host materials.

A heterometallic cluster [Ag6Au6(ethisterone)12] of an unprecedented topology was synthesized and characterized. A sensitive and specific probe for estrogen receptor α (ERα) has been developed for the first time based on the enhancement of the Ag6Au6 luminescence., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of highly phosphorescent PtAg2 heterotrinuclear alkynyl complexes with bis(diphenylphosphinomethyl)phenylphosphine (dpmp) were prepared and characterized structurally. The solution phosphorescence with various emitting colors is systematically modulated by modifying substituents as well as π-conjugated systems in aromatic acetylides. The crystals, powders, or films exhibit reversible stimuli-responsive phosphorescence changes upon exposure to vapor of MeCN, pyridine, DMF, etc., resulting from perturbation of d(8)-d(10) metallophilic interaction in the excited states as a consequence of the formation/disruption of Ag-solvent bonds. Both experimental and time-dependent density functional theory (TD-DFT) studies demonstrate that d(8)-d(10) metallophilic interaction exerts a crucial role on phosphorescent characteristics due to the PtAg2 cluster-based (3)[d → p] state. This study affords a paradigm for phosphorescence modulation in d(8)-d(10) heteronuclear complexes.

A new eulytite-like orthophosphate Pb(3)Bi(PO(4))(3), was synthesized by the high temperature solution growth (HTSG) method and characterized by X-ray single crystal diffraction, powder diffraction and electron microscopy. It crystallizes in the acentric cubic space group (I4[combining macron]3d). The pure-phase powders of Pb(3)Bi(PO(4))(3), Ba(3)La(PO(4))(3) and Ba(3)Bi(PO(4))(3) were also prepared by the high temperature solid reaction method. Second harmonic generation (SHG) measurements revealed that the optical response signals of Pb(3)Bi(PO(4))(3) and Ba(3)Bi(PO(4))(3) are about 3.0 and 0.5 times that of KH(2)PO(4) (KDP), respectively, and both are phase-matchable. The SHG signal of Ba(3)La(PO(4))(3) is very weak. Our studies indicate that the enhancement of the nonlinear optical response is mainly due to the contribution from the irregular PbO(6) and BiO(6) octahedra due to the 6s(2) lone electron-pair stereochemical activity in eulytite-like orthophosphates. Additionally, the calculated band structure and density of states also provide evidence that the charge transfers within irregular octahedral of Pb/BiO(6) make a significant contribution to the nonlinear optical response.

Objective: To clarify the relationship between the expression of alpha- and beta-isoform of corticosteroid receptors (CS) in peripheral blood mononuclear cell (PBMC) and response to corticosteroid in patients with allergic rhinitis (AR)., Methods: Semi-quantitative RT-PCR was used to detect the expression of CS-alpha, beta in PBMC in patients with AR and to observe the different responses to corticosteroid in controls. Immunocytochemical assay was used to detect the expression of protein of CS-alpha and CS-beta., Results: 1) The expression of CS-alpha mRNA was detected in the sensitive group and the resistant group of patients with AR and the controls with CS-alpha/GAPDH mRNA (x +/- s) 1.15 +/- 0.75, 1.63 +/- 0.78, 1.27 +/- 0.51 respectively. 2) The expression of CS-beta mRNA in PBMC in the resistant group of patients with AR was significantly higher than that in the sensitive group and the controls (P < 0.05), with CS-beta/GAPDH mRNA 1.42 +/- 0.73, 0.82 +/- 0.59, 0.80 +/- 0.68 respectively. 3) The number of CS-beta-positive PBMC in the resistant group was significantly higher than that in the sensitive group and the controls (P < 0.01), with the number of CS-beta-positive PBMC 28.8% +/- 9. 9%, 5.9% +/- 3.2%, 5.5% +/- 6.8% respectively., Conclusions: It is shown that the excessive expression of CS-beta may serve as a novel predictor of corticosteroid resistance in patients with AR.