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With high‐temperature solid‐state reaction method, a series of Lu2Sr(1−x)Al4SiO12:xEu2+ phosphors have been synthesized. With Rietveld refinement method, the crystal structure of Lu2SrAl4SiO12 has been refined. Under the excitation of the ultraviolet and violet band light, Lu2Sr(1−x)Al4SiO12:xEu2+ emits the Eu2+ characteristic blue broadband light. The photoluminescence properties of concentration quenching, emission peak shift, reflectance spectra, and luminescence decay have been investigated. With the structure analyses, the corresponding physical mechanisms have been discussed. With the increased temperature, this phosphor shows well thermal stabilities. For the xEu = 0.06, 0.08, and 0.1 phosphors, the strong anti‐thermal quenching performance has been observed. The reason for the anti‐thermal quenching of this phosphor has been discussed. The trap capture mechanism may be the suitable physical mechanism to explain the anti‐thermal quenching of this phosphor. This phosphor shows the potential applications in the white LED lighting fields. [ABSTRACT FROM AUTHOR]

Two new tfmpiq-based bis-cyclometalated iridium(III) complexes, [(tfmpiq)2Ir(imdzppo)] (2a) and [(tfmpiq)2Ir(idzpo)] (2b) (where tfmpiq = 1-(4-(trifluoromethyl)phenyl)isoquinoline, imdzppo = 2-(imidazo[1,2-a]pyridin-2-yl)phenol, idzpo = 2-(2H-indazol-2-yl)phenol), have been synthesized and fully characterized. The single crystal structure of 2b has been determined. The relationship between the structures and photophysical properties of both complexes are considered, and the DFT calculations have been used to further support the deduction. These Ir(III) complexes emit red light with quantum yields of 39.9-51.9% in degassed CH2Cl2 solution at room temperature. Also, their emission originates from a hybrid 3MLCT/3LLCT/3LC excited state. All these results show that iridium(III) complexes 2a-2b are suitable for red-phosphorescent materials in OLEDs. [ABSTRACT FROM AUTHOR]

Two new iridium(III) complexes were synthesized and fully characterized, [(bo)2Ir(pzpy)] (2a) and [(bo)2Ir(pzpyz)] (2b) (where bo = 2-phenylbenzo[d]oxazole, pzpy = 2-(1H-pyrazol-3-yl)pyridine, pzpyz = 2-(1H-pyrazol-3-yl)pyrazine). The single crystal structures of 2a-2b have been determined. Considering the relationship between their structures and photophysical properties, DFT calculations have been used to further support this inference. These Ir(III) complexes emit from the excited state of ³MLCT/³LLCT in the green and yellow region, and the quantum yields in the degassed CH2Cl2 solution at room temperature are 35.2% and 46.1%. Theoretical and experimental results show that iridium(III) complexes 2a-2b are promising phosphorescent material. [ABSTRACT FROM AUTHOR]

Nicotinic acid (NA), known as vitamin B3, has been widely studied in pharmaceutical science. Herein, three salts derived from NA and (1R,2R)‐1,2‐diphenylethylenediamine (DPEN), including one solvent‐free salt (DPEN)(NA)2 and two solvated salts, (DPEN)(NA)2(EA) and (DPEN)(NA)2(ACN) (EA: ethyl acetate, ACN: acetonitrile), have been obtained and characterized by solid‐state techniques. By the investigation of single‐crystal structures, the synthons, acid–ammonium heterodimer and Nammonium—H...Npyridine between functional groups of 1,2‐diphenylethylenediammonium and NA are revealed and further identified using Hirshfeld surface analysis. The utility of the synthons is further demonstrated by making salts with the NA isomer, isonicotinic acid. Here the synthon occurrences in cocrystals/salts of NA (including NA derivatives) and diamine coformers reported in the Cambridge Structure Database (CSD) are compared. The robustness of acid–ammonium heterodimer and Nammonium—H...Npyridine is investigated by a search of the CSD. The NA salts also show their improved solubility in pH 1.2, 4.5 and 6.8 buffer mediums compared with pure NA material. The crystal structures and solubilities of three nicotinic acid salts with (1R,2R)‐1,2‐diphenylethylenediamine are discussed and an analysis of synthon preference is provided. [ABSTRACT FROM AUTHOR]

Graphical abstract A new Co(II) compound, [Co 2 (DIPT) 4 (PClA) 2 Cl 2 ]·H 2 O (NCl-1) (DIPT = 2-(2,4-dichlorophenyl) -1H-imidazo [4,5–f]-[1,10]phenanthroline, HPClA = 3-(2-chlorophenyl)acrylie), have been successfully synthesized under mild hydrothermal conditions. By hydrogen bond and π-π stacking interactions constitute a stable three-dimensional space structure. The luminescent properties of the NCl-1 dispersed in different solvents have been investigated systematically, demonstrating unique selectivity for the detection of MeOH via a fluorescence quenching mechanism. The luminescent intensity of NCl-1 was selectively quenched by Fe3+ ions. In addition, the magnetic property of NCl-1 is investigated, which shows the anti ferromagnetic behavior induced by the external field. Highlights • One new Co(II) MOF have been synthesized. • The compound demonstrates unique selectivity for MeOH and Fe3+ ions. • The magnetic study reveals the dominant anti ferromagnetic interactions. Abstract A new coordination Co(II) complex, namely, [Co 2 (DIPT) 4 (PClA) 2 Cl 2 ]·H 2 O (NCl-1) (DIPT = 2-(2,4-dichlorophenyl) -1H-imidazo [4,5–f]-[1,10]phenanthroline, HPClA = 3-(2-chlorophenyl)acrylie) has been synthesized under solvothermal conditions and structurally characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction analysis, nitrogen adsorption analysis and powder X-ray diffraction. NCl-1 constructed by six coordinated mode with metal center and connected different ligands and ions, exhibits a three-dimensional structure under interactions of hydrogen bond and π-π stacking interactions. The luminescence explorations demonstrated that NCl-1 exhibits highly selective and sensitive sensing for organic solvents (MeOH) and metal ion (Fe3+). Furthermore, magnetic analysis indicated that NCl-1 also own the property of anti ferromagnetic. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, namely [Zn2(phen)2(DHTA)]·2H2O (1) and [Zn2(PHDI)2(DHTA)]·2H2O (2) (phen = 1,10-Phenanthroline, PHDI = 1,10-Phenanthroline-5,6- dione, DHTA = 2,5-dihydroxyterephthalic acid) have been synthesized under hydrothermal conditions. The structures have been determined by single crystal X-ray diffraction, thermal gravimetric analysis, infrared spectrum and luminescent properties. The X-ray diffraction analysis revealed the coordination modes of Zn(II) centers from complexes (1) and (2) are different. In (1), there are unusual five coordinated and six coordinated Zn(II) ions. In (2), the center is four coordinated Zn (II). Through these coordination modes of Zn centers and the π-π stacking interactions of organic ligands, the two complexes are all connected to three-dimensional supramolecular networks. The solid-state photoluminescence properties of (1) and (2) have been investigated. The emission peaks are located at 538 and 603 nm, the emissions may be attributed to the metal-to-ligand charge-transfer. The quantum-chemical calculations have been performed on ‘molecular fragments’ extracted from the crystal structure using the B3LYP method in Gaussian 09. [ABSTRACT FROM AUTHOR]

C9H10CeO11, triclinic, P1̄ (no. 2), a = 6.9100(14) Å, b = 9.1700(18) Å, c = 10.720(2) Å, α = 69.53(3)°, β = 83.56(3)°, γ = 87.01(3)°, V = 632.3(2) Å3, Z = 2, Rgt(F) = 0.0265, wRref(F2) = 0.0487, T = 298(2) K. [ABSTRACT FROM AUTHOR]

For the research of the thermometric performance, a series of Sr 2 Y 8(1- x - y) (SiO 4) 6 O 2 : x Ce3+, y Tb3+ phosphors were synthesized with the solid-state reaction method at N 2 /H 2 atmosphere. The crystal structure, room and high temperature photoluminescence spectra, luminescence decay, CIE variation, energy transfer and thermometric performance have been investigated. With the ultraviolet light excitation, both the Ce3+ broadband spectrum and Tb3+ line spectra have been observed. With the increase of the Tb3+ concentration, the emission color chromaticity varies from dark blue to bright green for the series of Sr 2 Y 8(1–0.07 -y) (SiO 4) 6 O 2 :0.07Ce3+, y Tb3+ phosphors. Under high temperature, the Ce3+ emission intensity quenches faster than that of Tb3+. Based on the different temperature quenching speeds of Ce3+ and Tb3+, the fluorescence intensity ratio technique was used to evaluate the thermometric performance of the series of Sr 2 Y 8(1–0.07- y) (SiO 4) 6 O 2 :0.07Ce3+, y Tb3+ phosphors. During the temperature range of 298–498 K, the maximum relative sensitivity values of the phosphors of y Tb = 0.05, 0.08, 0.1, 0.15, 0.2, 0.25 were calculated as 0.65, 0.69, 0.74, 0.71, 0.66, 0.6% K−1, which are much better than the recommended value of 0.30% K−1 for the practical application. The physical mechanisms for the Ce3+/Tb3+ excitation and emission, energy transfer and temperature quenching have been discussed. Sr 2 Y 8(1- x - y) (SiO 4) 6 O 2 : x Ce3+, y Tb3+ phosphors are the candidate thermometric probes for the non-contact temperature sensing applications. [Display omitted] • The crystal structure of Sr 2 Y 8(1- x - y) (SiO 4) 6 O 2 : x Ce3+, y Tb3+ has been refined and analyzed. • The physical mechanisms for the photoluminescence, the energy transfer and the thermal quenching have been discussed. • The reason for the different quenching speed of the emission of Ce3+ and Tb3+ has been revealed. • With FIR method, the thermometric performance of Sr 2 Y 8(1- x - y) (SiO 4) 6 O 2 : x Ce3+, y Tb3+ phosphors has been evaluated. [ABSTRACT FROM AUTHOR]

C37H35Ag2N5O6, monoclinic, C2/c (no. 15), a=25.806(2) Å, b=9.3041(3) Å, c=18.0702(17) Å, β=130.346(15)°, V =3306.7(4) Å3, Z =4, Rgt(F)=0.0426, wRref(F2)=0.0983, T =296(2) K. [ABSTRACT FROM AUTHOR]

C20H20N2O3, orthorhombic, Pbca (no. 61), a=9.1300(18) Å, b=16.170(3) Å, c=24.000(5) Å, V =3543.2(12) ų, Z =8, Rgt(F)=0.1274, wRref(F2)=0.1434, T =293 K. [ABSTRACT FROM AUTHOR]

Abstract Indomethacin (Indo) and naproxen (Nap) belong to Biopharmaceutical Classification System (BCS) class II drugs, which permeate membranes well but are poorly soluble. Two pharmaceutical salts hydrate of Indo and Nap with (1R,2R)-1,2-diphenylethylenediamine (DPEN) were obtained using solution crystallization. Both salts, (DPEN) 2 ·(Indo) 2 ·(H 2 O) 2 and (DPEN) 1 ·(Nap) 1 ·(H 2 O) 0.5 , were characterised using various solid-state characterisation techniques such as single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Raman spectra. The structure analysis shows that DPEN is monocation as only one amine is protonated into ammonium. The Indo , DPEN and water molecules form one-dimensional hydrogen bond chains through extensive N H⋯O, N H⋯N and O H⋯N interactions. The solubility study shows that the two salts are more soluble in pH 1.2, 4.5 and 6.8 buffer mediums compared with pure raw materials. Solubility thermodynamics calculation was carried out to further understand the solubility properties of two salts. Graphical abstract Pharmaceutical salts of Indometacin (Indo) and naproxen (Nap) enhanced solubility in pH = 1.2, 4.5 and 6.8 buffer. Image 1 Highlights • Two new pharmaceutical salts (indometacin and naproxen) were obtained. • Solid state properties, such as stabilities and solubility have been investigated. • Distribution of salts via solubility thermodynamics calculation has been evaluated. [ABSTRACT FROM AUTHOR]

C42H42F2N2O6, monoclinic, P21/c (no. 14), a = 20.159(3) Å, b = 8.3357(10) Å, c = 21.372(3) Å, β = 103.130(3)°, V = 3497.4(8) Å3, Z = 4, Rgt(F) = 0.0414, wRref(F2) = 0.1083, T = 113(2) K. [ABSTRACT FROM AUTHOR]

Although femtosecond laser microfabrication is one of the most promising three-dimensional (3D) fabrication techniques, it could suffer from low fabrication efficiency for structures with high 3D complexities. By using etching as a main assistant technique, the processing can be speeded up and an improved structure surface quality can be provided. However, the assistance of a single technique cannot satisfy the increasing demands of fabrication and integration of highly functional 3D microstructures. Therefore, a multi-technique-based 3D microfabrication method is required. In this paper, we briefly review the recent development on etching-assisted femtosecond laser microfabrication (EAFLM). Various processing approaches have been proposed to further strengthen the flexibilities of the EAFLM. With the use of the multi-technique-based microfabrication method, 3D microstructure arrays can be rapidly defined on planar or curved surfaces with high structure qualities. [ABSTRACT FROM AUTHOR]

We report a quantitative understanding of the reduction kinetics responsible for the formation of Pd-Pt bimetallic nanocrystals with two distinctive structures. The syntheses involve the use of KBr to manipulate the reaction kinetics by influencing the redox potentials of metal precursor ions via ligand exchange. In the absence of KBr, the ratio between the initial reduction rates of PdCl42- and PtCl42- was about 10.0, leading to the formation of Pd@Pt octahedra with a core-shell structure. In the presence of 63 mM KBr, the products became Pd-Pt alloy nanocrystals. In this case, the ratio between the initial reduction rates of the two precursors dropped to 2.4 because of ligand exchange and, thus, the formation of PdBr42- and PtBr42-. The alloy nanocrystals took a cubic shape owing to the selective capping effect of Br- ions toward the {100} facets. Relative to the alloy nanocubes, the Pd@Pt core-shell octahedra showed substantial enhancement in both catalytic activity and durability toward the oxygen reduction reaction (ORR). Specifically, the specific (1.51 mA cm-2) and mass (1.05 A mg-1 Pt) activities of the core-shell octahedra were enhanced by about four- and three-fold relative to the alloy nanocubes (0.39 mA cm-2 and 0.34 A mg-1 Pt, respectively). Even after 20000 cycles of accelerated durability test, the core-shell octahedra still exhibited a mass activity of 0.68 A mg-1 Pt, twice that of a pristine commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

C42H42N2O6, monoclinic, P21/c (no. 14), a = 6.9848(14) Å, b = 20.816(4) Å, c = 11.543(2) Å, β = 99.745(5)°, V = 1654.1(6) Å3, Z = 2, Rgt(F) = 0.0377, wRref(F2) = 0.1019, T = 113(2) K. [ABSTRACT FROM AUTHOR]

C40H50N2O4, monoclinic, P21/c (no. 14), a = 10.355(2) Å, b = 17.809(4) Å, c = 8.9354(16) Å, β = 97.101(4)°, V = 1635.2(5) Å3, Z = 2, Rgt(F) = 0.0453, wRref(F2) = 0.1270, T = 113 K. [ABSTRACT FROM AUTHOR]