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Herein, a new mechanism, namely, crystalline phase recognition (CPR), is proposed for the single-crystal-to-single-crystal (SCSC) transition of metal halides. Chiral β-[Bmmim]2 SbCl5 (Bmmim=1-butyl-2,3-methylimidazolium) can recognize achiral α-[Bmmim]2 SbCl5 on the basis of a key-lock feature through intercontact of their single crystals, resulting in a domino phase transition (DPT). The concomitant photoluminescence (PL) switching enables observation of the DPT in situ. The liquid eutectic interface, stress-strain transfer, and feasible thermodynamics are key issues for the CPR. DFT calculations and PL measurements revealed that the optical absorption and emission of the isomers mainly originate from [SbCl5 ]2- anions. The structural effects (e.g., supramolecular interactions and [SbCl5 ]2- distortion) on the optical emission are clarified. As a novel type of stimuli response, the CPR-induced DPT and luminescence switching exhibit potential for application in advanced time-resolved information encryption.

Although luminescent indium(III) based halide perovskites have been widely investigated, the study of emissive indium(III) halide hybrids is limited. Three indium(III) chloride hybrids based on a bpym ligand were synthesized, namely [EPy]2[InCl4(bpym)InCl4]·DMF (1), [EPy]2[InCl4(bpym)InCl4] (2), and [BPy]2[InCl4(bpym)InCl4] (3) (EPy = N-ethylpyridinium; BPy = N-butylpyridinium; bpym = 2,2′-bipyrimidine). They all exhibit a zero-dimensional structure, in which the ligand bpym interconnects two [InCl4]− to form a [InCl4(bpym)InCl4]2− anion that is further charge-compensated by the corresponding pyridinium cations. This is the first time using bpym to coordinate with an In atom. At 298 K, 1 exhibits a weak emission at 600 nm while 2 and 3 exhibit emissions peaking at 500 nm and 540 nm, respectively. Interestingly, the DMF solvent molecule in 1 can be removed by heating, thus resulting in the structural transformation of 1 into 2 together with a photoluminescence (PL) change. Density functional theory (DFT) calculations confirm that halogen-to-ligand charge-transfer (HLCT) occurs in the emission process. To the best of our knowledge, this is the first report on PL of ionic indium(III) halide hybrids incorporating organic ligands.

Compound [C5mim][Mim]2[SbCl6] (1; [C5mim]+ = 1-pentyl-3-methylimidazolium; [Mim]+ = N-methylimidazolium) with dual cations exhibits the first case of deep-red emission in [SbCl6]3--based 0D OIMHs. Anion distortion due to high disequilibrium of supramolecular interactions is revealed to be responsible for the extremely large Stokes shift of 335 nm and FWHM of 210 nm in the emission.

Three isomorphic ionic bismuth(III) halides were synthesized, utilizing 2,2′-bipyridyl-1,1′-dioxide (bp2do) as the organic ligand decorated on the halobismuthate(III) moieties, namely, [Ammim][BiBr4(bp2do)] (1, Ammim = 1-allyl-2,3-dimethylimidazolium), [Ammim][BiCl4(bp2do)] (2) and [Amim][BiCl4(bp2do)] (3, Amim = 1-allyl-3-methylimidazolium). They all crystallize in the space group of Pca21 with a similar supramolecular packing mode. However, the average adjacent Bi–Bi distances are slightly different, that is 1 > 2 > 3. Moreover, they possess different phosphorescence quantum yields (QYs) with 0.38% for 1, 27.83% for 2 and 34.76% for 3. Note that the QY of 3 remains the highest for bp2do-based halobismuthate hybrids. Their phosphorescence originates from the organic ligand bp2do, in which an inorganic-to-organic charge transfer (IOCT) process exists, as confirmed by density functional theory (DFT) calculations. The three compounds possess X-ray scintillation properties. Eventually, a WLED could be fabricated by mixing commercial nitride red phosphor with cyan-emitting 3. This study provides a method for the synthesis of organic ligand based ionic bismuth halide hybrids with higher QYs, and enriches X-ray scintillation materials.

Three bismuth(III) bromide hybrids based on 2,2′-bipyridyl-1,1′-dioxide (bp2do) were obtained by a solvothermal method, namely Bi2Br6(bp2do)2 (1), Bi2Br6(bp2do)2·0.5CH3CN (2), and [PP14][BiBr4(bp2do)] (3, PP14 = 1-butyl-1-methylpiperidinium). 1 features a centrosymmetric [Bi2Br6O4] dimer, in which two identical [BiBr4O2] octahedra edge-share two Br atoms; 2 contains a [Bi2Br6O4] dinuclear unit with a unique configuration, in which a [BiBr4O2] octahedron face-shares one Br and two O atoms with a [BiBr3O4] pentagonal-bipyramid. Moreover, the metal–ligand linking mode adopted in 2 has not been reported before. The choice of organic solvents could induce different Bi–Br–bp2do geometries with a dimer in 1 and a dinuclear unit in 2. Introduction of ionic liquid cations resulted in the ionic compound 3 featuring a mononuclear [BiBr4(bp2do)] unit. A more rigid environment with more hydrogen bonds leads to visible green phosphorescence with long lifetime for 3 under UV light. The three compounds possess similar phosphorescence peaks at 77 K, which originates from inorganic-to-organic charge transfer (IOCT) as confirmed by density functional theory (DFT) calculations.

Two chlorobismuthate hybrids incorportating ionic liquid cations (ILCs) with second-level room-temperature phosphorescence (RTP), namely [Emim]BiCl4(bp2do) (1) and [Emmim]BiCl4(bp2do) (2) (Emim = 1-ethyl-3-methylimidazolium, Emmim = 1-ethyl-2,3-dimethylimidazolium, bp2do = 2,2′-bipyridyl-1,1′-dioxide), were obtained. The decrease in the number of substituents in the ILCs largely enhanced the phosphorescence quantum yield (QY) from 2.31% for 2 to 25.05% for 1, owing to the more compact structure of 1. The two compounds possess uncommonly different temperature-dependent emission peak shifting behaviors, which could be ascribed to whether the electron-phonon interactions or the exciton localization at high energy is dominant. Density functional theory (DFT) calculations show that the optical absorptions for both compounds originate from inorganic moiety to organic moiety charge transfer (IOCT). X-ray scintillation was observed for both compounds, which is the first report on inorganic–organic halobismuthate hybrids. Finally, 1 with higher QY was fabricated into a luminescent thin flim, letters and a bendable round wafer with polyacrylonitrile (PAN). This work provides new insight on RTP materials and X-ray scintillation materials involving bismuth halides.

Cobalt-based phosphate/phosphonates are a class of promising water oxidation catalysts at neutral pH. Herein, we reported a facile hydrothermal synthesis of various nanostructured cobalt phenylphosphonates. It is found that the number of hydroxyl group of structure-directing reagent is crucial for the construction of 3D hierarchical structures including hierarchical nanosheet flower-like assemblies and nanothorn microsphere. These samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, infrared, and X-ray photoelectron spectroscopy techniques. They can act as highly efficient electrocatalysts for the oxygen evolution reaction at neutral pH. Among these, hierarchical cobalt phenylphosphonate nanothorn flowers present excellent performance, affording a current density of 1 mA cm−2 required a small overpotential of 393 mV. This work offers a new clue to develop high-performance metal phosphonate/phosphate catalysts toward electrochemical water oxidation.

Two bismuth(III) halides hybrids with room-temperature phosphorescence (RTP), namely, [BPy]2[Bi2Cl8(bpym)] (1, BPy = N-butylpyridinium) and [EPy]2[Bi2Cl8(bpym)] (2, EPy = N-ethylpyridinium), were s...

The correlation between metal coordination and electrocatalytic water oxidation performance is elusive in many cobalt-based materials. Herein, we designed an ideal Co phosphate-based platform to explore the effect of coordination environment on oxygen evolution reaction (OER) activity. The cobalt geometry was modulated from octahedral to tetrahedral by simple removal of water ligands in Co3 (PO4 )2 ⋅8 H2 O. Other features except the coordination structure in the two autologous materials remain similar. The two analogues display the same OER kinetics, but the anhydrous Co3 (PO4 )2 exhibits a greatly enhanced OER activity. On the basis of Raman and operando XAS results, the higher intrinsic activity of the Co tetrahedral sites is because they facilitate the formation of active high valent cobalt (hydr)oxide intermediates during OER. This work not only brings insights of OER on Co-based electrocatalysts but also provides a reference system to study the effect of metal geometry on electrocatalysis.

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Zero-dimensional (0D) organic–inorganic hybrid metal halides (OIMHs) containing multiple halometallate species (HMSs) have received extensive attention due to their capability to achieve multifunctional photophysical characteristics. Herein we report a lead-free 0D-OIMH compound, namely [Emim]8[SbCl6]2[SbCl5] (1, Emim = 1-ethyl-3-methylimidazolium), which is the first crystal containing two distinct mononuclear [SbXn]3−n units in one single structure. The optical absorption, temperature/excitation-variable photoluminescence (PL) and PL decay were studied. 1 exhibits a broad emission centered at 577 nm, which is analyzed to be a combination of the emissions from [SbCl6]3− and [SbCl5]2−. The structural effects including Sb⋯Sb distances and polyhedral distortion of [SbXn]3−n on the PL of antimony-based 0D-OIMHs are discussed in detail. This work would provide guidance for constructing Sb-based 0D OIMHs composed of multiple halometallate species.

CsMnCl3(H2O)2 (CMCH) has been widely investigated for magnetic and optical applications, including anti-Stokes photoluminescence, microwave absorption, and magnon-assisted optical transitions. Herein, CMCH crystals, which are colorless and transparent (unlike the pink crystals reported previously), were obtained through a unique approach. Consequently, a high-resolution optical absorption spectrum and distinct thermal behavior were observed. The reversible (de)hydration of CMCH being accompanied by photoluminescence switching (mainly in terms of the color temperature) was rationalized using crystal structure analysis. As a result, water-soluble CMCH could be applied as a moisture-responsive luminescent ink. Moreover, density functional theory (DFT) calculations were performed to understand the optical absorption of CMCH.

The discovery of new halide perovskite-type structures could favor the exploration of optoelectronic materials, as in the case of double perovskites applied in solar cells, light-emitting diodes, and X-ray detectors. In this work, we propose a strategy for designing quadruple perovskites by heterovalent cation transmutation from double perovskites. Two stable quadruple perovskite halides, i.e., Cs4CdSb2Cl12 and Cs4CdBi2Cl12, with a vacancy-ordered three-dimensional (3D) crystal structure were predicted through symmetry analysis and density functional theory (DFT) calculations. The title perovskite halides are also electronically 3D with direct forbidden bandgaps. Following the indication provided by the DFT results, Cs4CdSb2Cl12 and Cs4CdBi2Cl12 as unique quadruple perovskites were successfully synthesized by a solvothermal method. The steady-state photoluminescence (PL) shows wide emission, while the transient PL exhibits carrier recombination lifetime on the order of microseconds at low temperature. The quadruple perovskite halides provide an alternative platform for promising optoelectronic material design in addition to simple and double perovskites.

The hydrothermal reactions of divalent metal salts with 4-HOOC–C6H4–CH2–NH2CH2PO3H2 (H3L) led to four Metal-organic phosphonates (MOPs), namely, Ni(HL)(H2O)2 (1), Cd(HL) (2), CdCl(H2L) (3), and Pb1.5Cl2(H2L) (4). All these compounds exhibited 2D layer substructures with various features based on metal centers and –PO3 groups of the ligands. Differently, the layers cross-linked each other in compounds 1 and 4 via hydrogen bonds generating 3D supramolecular frameworks. While in compounds 2 and 3, they were connected by carboxylate group of the ligands to form 3D pillared-layer frameworks. Such differences were related to the coordination mode of the metal centers, and the pH of the reaction system also played a important role on the coordination ability of the ligands. The magnetic properties reveal the presence of ferromagnetic interactions in compound 1 through a Ni–O–P–O–Ni five-member chain. Luminescent measurements indicate that compounds 2–4 each displays strong blue fluorescent emissions.

This case report describes idiopathic ventricular tachycardia (VT) originating from the anterolateral site of mitral annulus. Radiofrequency (RF) energy application at an endocardial site of mitral annulus could not eliminate the tachycardia. The earliest epicardial activation preceding the onset of the QRS complex by 34 ms was found at the great anterior cardiac vein just opposite to the endocardial ablation catheter, pace mapping provided an identical (12/12) match with the VT morphology at the site, and RF ablation effectively eliminated the VT from the great cardiac vein within the coronary venous system. (PACE 2012; 35:e120–e123)

Background Development of experimental animal models has played an important role in understanding the mechanisms of cardiac memory. The purpose of this study was to evaluate a new canine model of cardiac memory using endocardial ventricular pacing via internal jugular vein. Methods Twelve Beagle dogs underwent placement of a permanent ventricular pacemaker mimicking the use of pacemakers in humans and induction of cardiac memory by endocardial ventricular pacing. Results Cardiac memory was achieved in 11 of 12 attempts overall. Procedural mortality due to cardiac tamponade (n = 1) occurred in the first attempt. The T-wave memory persisted for 96 ± 17 minutes and 31 ± 6 days in the short-term and long-term cardiac memory groups, respectively. There were no significant differences in the heart rate, blood pressure and echocardiographic parameters in the animals between before and after ventricular pacing in the short-term and long-term cardiac memory groups. No significant pathologic changes with the light microscopy were found in the present study in all dogs. Conclusion The model does require surgery but is not as invasive as an open-chest model. This canine model can serve as a useful tool for studying mechanisms of cardiac memory.

Oxidative stress has been implicated in the pathogenesis of acute myocarditis. The imbalance between the occurrence of reactive oxygen species and the cellular antioxidant defense mechanism plays a key role in myocardial injury of viral myocarditis. Carvedilol, a nonselective β-adrenoceptor antagonist with additional α 1 -adrenergic blocking and antioxidant properties, has been shown to be cardioprotective in experimental myocarditis. However, the expression of 4-hydroxy-2-nonenal (4-HNE), the most reliable marker of lipid peroxidation, has not been studied, and the antioxidative effects of carvedilol have not been investigated in the setting of acute viral myocarditis. This study was therefore designed to determine whether levels of lipid peroxides are elevated in the myocardium and whether carvedilol reduces the lipid peroxidation level and increases antioxidant enzyme activities. In a coxsackievirus B3 murine myocarditis model (Balb/c), effects of carvedilol and metoprolol on 14-day survival rate, myocardial histopathological changes, cardiac function, the expression of 4-HNE, virus titers, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidases (GSH-Px) activities were studied. Lipid peroxidations including 4-HNE and MDA, were elevated in murine coxsackievirus-induced acute viral myocarditis. Carvedilol, but not metoprolol, improved survival, reduced lipid peroxidations including 4-HNE and MDA, and increased antioxidant enzyme activities including SOD and GSH-Px with amelioration of acute viral myocarditis. These results show that carvedilol but not metoprolol exerts some of its beneficial effects by inhibiting peroxidants.

Pulse pressure (PP) is emerging as a major pressure predictor of cardiac disease. However, there are two major limitations for PP as an evaluation index. First, PP has alterability in the same individual. Second, PP is "floating", it has no relation to an absolute BP level. In order to overcome the defects of PP, we propose a novel parameter, "pulse pressure/systolic pressure" called "pulse pressure index (PPI)" for assessment of cardiovascular outcomes. On the basis of elastic chamber theory, the following equation can be derived: PPI=pulse pressure/systolic pressure=(Cs-Cd)/(Cs-C(0)), (Cs, Cd and C(0), arterial compliance at systolic pressure, diastolic pressure and zero-pressure, respectively). PPI can overcome the defects of PP and become a useful index in clinical evaluation for assessment of cardiovascular outcomes.

Carvedilol, a nonselective beta-blocker with additional alpha1-adrenergic blocking and antioxidant properties, has been shown to be cardioprotective in experimental myocarditis. However, the antioxidative effects of carvedilol have not been investigated in the setting of acute viral myocarditis. Therefore, this study investigated whether carvedilol protects against viral myocarditis primarily by its antioxidant and/or antiinflammatory properties. In a coxsackievirus B3 murine myocarditis model (Balb/c), effects of carvedilol and metoprolol on myocardial histopathological changes, cytokine levels, virus titers, malondialdehyde (MDA), and superoxide dismutase (SOD) contents were studied. Carvedilol markedly attenuated myocardial lesions and increased interferon-gamma and interleukin-12 production (cytokines) on day 7 with concomitant reduction of myocardial virus replication. In addition, only carvedilol decreased the content of MDA and increased the content of SOD on day 14. Metoprolol as well as bunazosin (a higly selective alpha1-adrenergic blocking agent) had no significant effects in this model. The results indicate that the superior protection of carvedilol in this model is probably the result of its antioxidative effects and the upregulation of antiinflammatory cytokines.

Background RFCA has been established as an effective and curative therapy for severely symptomatic PVC from the outflow tract in structurally normal hearts. However, it is unknown whether PVCs originating from the left ventricular septum, are effectively eliminated by RFCA. This study aimed to investigate electrophysiologic characteristics and effects of Radiofrequency catheter ablation (RFCA) for patients with symptomatic premature ventricular contraction (PVC) originating from the left ventricular septum without including fascicular PVCs. Methods Characteristics of body surface electrocardiogram (ECG) and electrophysiologic recordings endocardiogram in a successful RFCA target were analyzed in 20 patients with symptomatic PVCs originating from the left ventricular septum. RFCA was performed using pace mapping and activation mapping. Results The QRS morphology of PVCs originating from the left ventricular septum is similar to that seen in fascicular tachycardia. Most of the PVCs originated from the left septum appears in the form of ventricular parasystole. The incidence of ventricular parasystole was 70%. Sustained ventricular tachycardia was not inducible by electrical stimulation and isoproterenol infusion in all 20 patients, ablation at the site recording the earliest Purkinje potential was not effective in all 20 patients, and Purkinje potentials were not identified at successful sites during point mapping. Sixteen patients were successful with RFCA using pace mapping and activation mapping, 3 failed, and 1 recurrent. Conclusion Although the ECG characteristics of the PVCs arising from the left ventricular septum are similar to that seen in fascicular tachycardia, the electrophysiologic characteristics are different between the two types of PVCs. The distinguishing characteristic of the PVCs is that Purkinje potentials were not present at the site of successful ablation, suggesting a myocardial as opposed to fascicular substrate. RFCA is an effective curative therapy for symptomatic PVCs originating from the left ventricular septum (not from the left anterior and posterior fascicle).