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Abstract This study focused on how the local structures in pure [N(CH3)4]2ZnBr4 crystal are affected by the partial replacement of Zn2+ ions with Cu2+ ions. The structures and phase transition temperatures TC of perovskite-type [N(CH3)4]2Zn1-x Cu x Br4 (x = 0, 0.5, 0.7, and 1) mixed crystals were almost unchanged by the partial doping of Cu2+ ions. The environments for the local structures of [N(CH3)4]2Zn1-x Cu x Br4 mixed systems were studied according to differences in the chemical shifts of the 1H magic angle spinning (MAS) NMR, 13C cross-polarization (CP)/MAS NMR, and 14N NMR spectra. The 1H and 13C NMR results showed that the local environments of 1H and 13C nuclei near TC are not affected by substituting Zn2+ ions with Cu2+ ions, whereas the 14N NMR results showed that the local environment is affected near TC. Consequently, the main indicators of the phase transition in [N(CH3)4]2Zn1-x Cu x Br4 are related to the ferroelastic characteristics with different orientations.

Reaction of Co(NCS)2 and Ni(NCS)2 with 4-tert-butylpyridine in ethyl acetate leads to the formation of mixed crystals of a layered compound with the composition [CoxNi1−x(NCS)2(4-tert-butylpyridine]n. The mixed crystal formation was investigated by a combination of atomic absorption spectroscopy, X-ray powder diffraction and IR spectroscopy. Magnetic and specific heat measurements prove dominating ferromagnetic exchange interactions within the layers and a ferromagnetic transition. Depending on the synthetic method, inhomogeneous samples were obtained, for which predominantly the large difference in the solubility of the homometallic compounds might be responsible. Very long reaction time leads to much better samples for which a distinct critical temperature is observed that increases smoothly with increasing Ni content. [ABSTRACT FROM AUTHOR]

Carrier mobility is one of the key issues for applications of organic semiconductors in electronic and optoelectronic devices. Organic single crystals possess much higher carrier mobility compared to amorphous films. However, unipolar properties with unbalanced hole and electron transporting ability have been a bottleneck for the high performance of organic single crystal‐based devices. Here, well‐balanced ambipolar organic single crystals are developed by mixing of n‐ and p‐type molecules with maintained single‐crystalline structures. Carrier mobility of the ambipolar single crystals is manipulated by tuning the mixing ratio, and nearly equal hole and electron mobility can be achieved. Highly efficient single crystal‐based organic light‐emitting devices (OLEDs) are demonstrated by employing the ambipolar crystals as the mixed host for a red emitter pentacene to realize efficient exciton confinement and energy transfer within the emissive layer. As a result, maximum luminance of 5467 cd m−2 and current efficiency of 2.82 cd A−1 are achieved, which represents, to the best of the authors' knowledge, the record performance for the organic single crystal‐based OLEDs to date. The strategy to manipulate the charge‐transport properties of the organic single crystals in this work represents a significant step toward practical applications of the organic single crystals in optoelectronics. [ABSTRACT FROM AUTHOR]

Using a combination of fluorescence and bright-field optical imaging, the solid-state packing structures of semi-confined two-layer spherical colloidal crystals were observed during modulation of an external AC electric field. Upon increasing field strength, the bottom layer of colloids (layer 1) transitioned from the entropically favored hexagonal packing structure with p6m symmetry to a square-packing structure with p4m symmetry. The packing structure of layer 2 was determined by the packing structure of layer 1, with layer 2 particles resting in, and moving in registry with, the low-energy interstitial sites of layer 1. Modulation of the field strength thus resulted in a reversible transition between a face-centered cubic crystal structure and a body-centered cubic crystal structure at low and high field strengths, respectively. These structures were found to be sensitive to the particle density in the wells, with vacancies and insertions leading to the formation of mixed crystal phases at high field strengths. [ABSTRACT FROM AUTHOR]

This paper presents a high-performance mixed controlled crystal oscillator. The digital-controlled part is based on a Pierce topology with switched-capacitor bank. Wide tuning range and high linearity are simultaneously achieved by combining discrete capacitors and a continuous voltage tuning varactor. The pull ability is around 99 ppm output frequency variation range. For noise reduction, the supply voltage of the mixed controlled crystal oscillator is regulated at 2.5 V by using on-chip low-drop regulators. The measured phase noise is −145 dBc/Hz at 1 kHz offset frequency by using a 40 MHz fundamental AT–cut crystal. The chip area is 3.6 mm2 for a 0.35 μm standard CMOS process with 3.3 V supply voltage and the power dissipation is 7 mW. [ABSTRACT FROM AUTHOR]

Reaction of 1,2‐di(tetrazol‐2‐yl)ethane (ebtz) with Fe(BF4)2⋅6 H2O in different nitriles yields one‐dimensional coordination polymers [Fe(ebtz)2(RCN)2](BF4)2⋅nRCN (n=2 for R=CH3 (1) and n=0 for R=C2H5 (2) C3H7 (3), C3H5 (4), CH2Cl (5)) exhibiting spin crossover (SCO). SCO in 1 and 3–5 is complete and occurs above 160 K. In 2, it is shifted to lower temperatures and is accompanied by wide hysteresis (T1/2↓=78 K, T1/2↑=123 K) and proceeds extremely slowly. Isothermal (80 K) time‐resolved single‐crystal X‐ray diffraction studies revealed a complex nature for the HS→LS transition in 2. An initial, slow stage is associated with shrinkage of polymeric chains and with reduction of volume at 77 % (in relation to the difference between cell volumes VHS−VLS) whereas only 16 % of iron(II) ions change spin state. In the second stage, an abrupt SCO occurs, associated with breathing of the crystal lattice along the direction of the Fe–nitrile bonds, while the nitriles reorient. HS→LS switching triggered by light (808 nm) reveals the coupling of spin state and nitrile orientation. The importance of this coupling was confirmed by studies of [Fe(ebtz)2(C2H5CN/C3H7CN)2](BF4)2 mixed crystals (2 a, 2 b), showing a shift of T1/2 to higher values and narrowing of the hysteresis loop concomitant with an increase of the fraction of butyronitrile. This increase reduces the capability of nitrile molecules to reorient. Density functional theory (DFT) studies of models of 1–5 suggest a particular possibility of 2 to adopt a low (140–145°) value of its Fe‐N‐C(propionitrile) angle. [ABSTRACT FROM AUTHOR]

This work reports experimental evidence of a photovoltaic effect in transparent UV‐selective Zn(O,S)‐based heterojunctions. Zn(O,S) has a strong interest for the development of UV‐selective solar cells with high transparency in the visible region, required for the development of nonintrusive building‐integrated photovoltaic (BIPV) elements as transparent solar windows and glass‐based solar façades. By anion alloying, Zn(O,S) mixed crystal absorbers can be fabricated with different sulfur content across the whole compositional range. This allows adjustment of the bandgap of the absorbers in the 2.7–2.9 eV region, maximizing absorption in the UV, while keeping a high level of transparency. Zn(O,S) alloys with composition corresponding to S/(S + O) content ratios of 0.6 are successfully grown by sputtering deposition, and first glass/FTO/NiO/Zn(O,S)/ITO device prototypes are produced. The resulting devices present an average visible transmittance (AVT) of 75% and present photovoltaic effect. By introducing a thin C60 film as electron transport layer (ETL), charge extraction is enhanced, and devices show an efficiency of 0.5% and an AVT > 69%. The transparency of these devices can potentially allow for their ubiquitous installation in glazing systems as part of nonintrusive BIPV elements or to power Internet of Things (IoT) devices and sensors as an integrated transparent component. [ABSTRACT FROM AUTHOR]

TlGaS2 and TlGaSe2 ternary semiconducting compounds have been of scientific interest due to their large ultrafast optical nonlinearity characteristics. These remarkable properties make them promising semiconducting materials in photonic applications. A series of (TlGaS2)x‒(TlGaSe2)1−x layered mixed crystals grown by Bridgman method were investigated from the standpoint of their Raman spectroscopy characteristics. Experimental Raman scattering study of crystals were reported in the frequency range of 80–400 cm−1 for compositions of x = 0, 0.25, 0.50, 0.75 and 1.0. The effects of crystal disorder on the line-width broadening of Raman-active modes were studied in detail. The asymmetry in the Raman line-shape was analyzed for two highest-frequency intralayer mode presenting two-mode behavior. It was shown that mixed crystal disorder effect is the major source for change of Raman line-shape with composition. [ABSTRACT FROM AUTHOR]

The Neoproterozoic Bijigou intrusion is one of the largest and well-differentiated Fe–Ti oxide-bearing layered intrusion in Central China, and hosts Fe–Ti oxide ore layers in the middle zone with a total thickness of ∼112 m. In order to examine the role of compaction and compositional convection on the solidification of a layered intrusion associated with the crystallization of large amounts of Fe–Ti oxides, we collected the samples from a drill core profile of the apatite-oxide gabbronorite unit above the main Fe–Ti oxide layer in the middle zone of the Bijigou intrusion and carried out a detailed study on the crystal size distributions (CSDs) and trace element compositions of the fluorapatite in the samples. The apatite-oxide gabbronorite unit is mainly composed of pyroxene and plagioclase with Fe–Ti oxides and fluorapatite interstitial to the silicates, and can be further divided into the lower and upper sections in terms of grain size, rare earth element (REE) concentrations of fluorapatite and stress deformation of minerals. In the lower section, the plagioclase and pyroxene of the rocks are often bent, fluorapatite crystals have grain sizes ranging from ∼0·10 × 0·30 mm to ∼1·00 × 2·50 mm and the average Ce concentration of the fluorapatite of each sample varies from 230 to 387 μg/g. In contrast, the plagioclase and pyroxene of the rocks from the upper section are sparsely bent, fluorapatite crystals range in size from ∼0·05 × 0·05 mm to ∼0·15 × 0·40 mm, and the average Ce concentration of the fluorapatite of each sample varies from 468 to 704 μg/g. Modeling results show that the fraction of trapped liquid (F TL) is ∼7% in the lower section and ∼15% in the upper section, and relatively elevated REE (e.g. Ce) concentrations of the fluorapatite of the upper section are thus likely attributed to the trapped liquid shift (TLS) effect. The TLS effect may have also enhanced the textural coarsening of the fluorapatite of the upper section, which is illustrated by a convex-upward curve for <0·1 mm crystals and a counter-clockwise rotation around a fixed point in the CSDs of the fluorapatite. The CSDs of the fluorapatite of the lower section, however, change from a steep slope for <0·25 mm crystals to a gentle slope for >0·25 mm crystals with a kinked trend akin to mixed crystal populations, which is interpreted as the exchange of interstitial liquid with the main magma body due to compositional convection. The different F TL and fluorapatite CSDs of the lower and upper sections indicate that the interstitial liquid may have been expelled from the crystal mush of the lower section more efficiently than from the upper section, which is likely controlled by both compaction and compositional convection. However, it was the compositional convection that dominated the expulsion of interstitial liquid in the whole apatite-oxide gabbronorite unit, indicating that compositional convection may prevail after the crystallization of large amounts of Fe–Ti oxides from interstitial liquid and weaken the role of compaction. [ABSTRACT FROM AUTHOR]

The nano SiC coatings were prepared on the surface of graphite by laser irradiation under different laser energy densities (7.07–14.15 kJ/cm2). The influence of laser energy density on the structure and quality of coatings was systematically investigated. The results show that laser irradiation can transform the preset micron-SiC particle coating into nano-SiC particle coating. The nano-SiC coating prepared by laser irradiation can effectively enhance the high temperature oxidation resistance of the graphite substrate. When the laser energy density is 7.07 kJ/cm2, the prepared coating displays a single crystal structure and a good morphology without cracks and spheroidization. The coating prepared under the laser density of 10.61 kJ/cm2 shows a mixed crystal structure with obvious spheroidization. Further increase the laser energy density to 14.15 kJ/cm2, the main structure of prepared coating turns to polycrystalline and obvious cracks can be observed. The cross-section analysis of coating prepared under laser energy density of 7.07 kJ/cm2 indicates that there existed elemental diffusion between the coating and the substrate which increased the adhesion of coating. The calculations based on the Arrhenius formula present that this prepared coating has higher activation energy and therefore it has better high temperature oxidation resistance than the other prepared coatings. [ABSTRACT FROM AUTHOR]

Rotational viscosity coefficient is an important material parameter affecting the dynamic response of liquid crystals. We evaluated the dynamic response of two series of mixed liquid crystals SCL17V33L00 and SCL17V28L00 with negative dielectric anisotropy on the basis of the accurate measurement of rotational viscosity. At the temperature of 25°C, 30°C and 35°C, the parallel and vertical dielectric constants of them were calculated from the dual-cell capacitance model and liquid crystal cell capacitance model. Then, the bend and splay elastic constants of them were determined by analysing the Fréedericksz transition threshold voltage in the vertically aligned nematic cell and comparing the liquid crystal layer capacitance–voltage curve through the finite-differential iteration method with experimental curve. At last, the rotational viscosity coefficients γ1 of them were obtained by performing dynamic response simulation using Visual Fortran software. As the temperature increases, the rotational viscosity coefficient of them decreases. Although the rotational viscosity coefficient of the second mixed liquid crystal was relatively large under the same temperature, the viscoelastic ratio coefficient was small, and the figure-of-merit was large, thereby resulting in a relatively fast dynamic response. [ABSTRACT FROM AUTHOR]

• Zn 2 SnO 4 thin films synthesized by electron beam evaporation were annealed at 500 °C. • Annealed Zn 2 SnO 4 thin films were irradiated with 120 MeV swift heavy ions of Ag+9 for different ion fluences. • The changes in crystal structure and optical properties have been observed after irradiation and are understood by Thermal Spike Model. The structural changes and their effect on optical properties have been studied in Zn 2 SnO 4 thin films irradiated by Ag9+ ions. The irradiation of thin films transforms the mixed crystal structures in to a single diffraction plane. In the XRD, the single peak is the result of atomic jump within the material due to the change in activation energy after irradiation. The XRD and SEM confirmed the modifications of lattice parameters and grains in accordance with the basic requirement of material to be used as transparent conducting oxides. In optical studies, the absorption spectra and Tauc plot confirm the neutralization of free electrons in conduction band minimum which results in an increase in the optical band gap for better transmission in visible range. The results indicate that the swift heavy ions passed from polycrystalline material synergistically with inelastic electronic energy loss to promote the formation of Zn 2 SnO 4 oriented in a single direction and lead to rapid phase transformation. [ABSTRACT FROM AUTHOR]

Environmental context: Antimony is classified as a priority pollutant and is increasingly detected in the environment as a result of various anthropogenic activities. Natural secondary iron minerals are important sinks for many toxic elements. We found that antimony promotes structural transformations in secondary iron minerals, and that antimony is then further immobilised by the newly formed iron mineral phases. Secondary iron minerals (SIMs), naturally formed in acid mine drainage (AMD), can serve as sinks to remove antimony (Sb) from the environment. In this study, we investigated the relationship between the structural characteristics and SbIII or SbV sorption behaviours of two different SIMs (neo-formed SIM (n-SIM) and mature SIM (m-SIM)). The results showed that both m- and n-SIMs were composed of mixed crystal phases, mainly schwertmannite, jarosite, goethite and ferrihydrite. Despite similar elemental compositions, they had different microstructures. m-SIM was a regular spheroid with a close-packed arrangement, while n-SIM was an incomplete irregular spheroid with ordered channels and a random loose arrangement. The initial SbIII or SbV sorption rate order was n-SIM > m-SIM. The maximum sorption capacities of n- and m-SIMs were 219.8 (SbIII) or 366.3 (SbV) mg g−1 and 160.3 (SbIII) or 114.9 (SbV) mg g−1 respectively, and n- and m-SIMs could both effectively remove Sb from natural wastewaters, while trace Sb levels remained. Sb immobilisation on SIMs occurred as a rapid endothermal and homogeneous sorption process. After Sb sorption, the SO42− and total Fe(aq) concentrations in the sample solutions significantly changed. X-ray diffraction (XRD) and Raman analyses confirmed that n- or m-SIM had transformed in the presence of Sb, even without FeII(aq), which indicated an important SIMs transformation-Sb immobilisation relationship. These findings are valuable for better understanding the Sb behaviours associated with natural SIMs and the short-term fate of Sb in the environment. Environmental context. Antimony is classified as a priority pollutant and is increasingly detected in the environment as a result of various anthropogenic activities. Natural secondary iron minerals are important sinks for many toxic elements. We found that antimony promotes structural transformations in secondary iron minerals, and that antimony is then further immobilised by the newly formed iron mineral phases. [ABSTRACT FROM AUTHOR]

Crystallization-driven self-assembly of three macrocyclic members of the cucurbit[n]uril family is reported. The largest cucurbit[10]uril serves as a host for the smallest cucurbit[5]uril forming an inclusion complex of the macrocycle-within-macrocycle type. This supramolecular ensemble undergoes cocrystallization with cucurbit[7]uril. Such unusual cocrystallization is explained by the strong tendency of all cucurbit[n]urils to associate via multiple C–H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The adamite-olivenite solid-solution series includes three mineral species (adamite, zincolivenite, and olivenite) defined by the proportions of copper and zinc in each of two ordered cation sites in the crystal structure. Adamite and zincolivenite are both orthorhombic, and olivenite is monoclinic; however, the symmetry change occurs at about 80 mole percent copper, so that the speciation for compositions between 75 and 80 mole percent copper is poorly defined. Once copper becomes the dominant cation (i.e., greater than 50 mole percent) in that site, the overall copper ratio (including both cation sites) exceeds 25 mole percent, and the mineral moves into the compositional range of zincolivenite. Once copper exceeds 50 mole percent in the second site (i.e., greater than 75 mole percent overall), however, the upper limit of copper content by which zincolivenite is defined is exceeded. Potentially, this introduces a further problem of nomenclature (although not an issue in the context of the current article); zincolivenite is defined as containing between 25 and 75 mole percent copper, but in synthetic members of the series the symmetry change from orthorhombic to monoclinic occurs at around 80 mole percent copper (Toman [27], [28]; see fig. 7). [Extracted from the article]

(1- x)[0.8Na 0.5 Bi 0.5 TiO 3 -0.2K 0.5 Bi 0.5 TiO 3 ]- x BiMn 2/3 Nb 1/3 O 3 ((1- x)NKBT- x BMN with x = 0–0.04) piezoceramics were prepared, the composition-dependent domain structure and domain switching under electric field and their effects on macroscopic electrical properties have been systematically investigated. At room temperature, though the ceramics persists rhombohedral-tetragonal mixed crystal structure, their domain structure evolves from dispersive island-like with average size of 80 nm for x = 0 to labyrinthian-like with average size of 120 nm for x = 0.0075, and then tends to be unobservable by forming polar nanoregions for x = 0.04. As the results, the x = 0.0075 ceramic shows enhanced ferroelectric and piezoelectric property. When compared with the x = 0 pristine counterpart, the saturated polarization, remnant polarization, piezoelectric coefficient, and electromechanical coupling factor of x = 0.0075 ceramic increase by 3%, 12%, 40%, and 20% to 43.2 μC/cm2, 31.2 μC/cm2, 147 pC/N, and 0.28. This work suggests that fine domain engineering is a promising way to further improve electrical property. [ABSTRACT FROM AUTHOR]

The unit cell of the title compound, [Zn(C17H18N3O4)2]·CH4O·C2H6O, contains two complex molecules related by an inversion centre, plus one methanol and one ethanol solvent molecule per complex molecule. In each complex, two deprotonated pyridine aroylhydrazone ligands {3,4,5-trimethoxy-N'-[1-(pyridin-2-yl)ethylidene]benzohydrazide} coordinate to the ZnII ion through the N atoms of the pyridine group and the ketamine, and, additionally, through the O atom of the enolate group. In the crystal, dimers are formed by π-π interactions between the planar ligand moieties, which are further connected by C···O and C···C interactions. The intermolecular interactions were investigated using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing that the most important contributions for the crystal packing are from H···H (44.8%), H···C/C···H (22.2%), H···O/O···H (18.7%) and C···C (3.9%) interactions. [ABSTRACT FROM AUTHOR]

Mixed crystals composed of two distinct gold isocyanide complexes are reported. Characterization of the mixed crystal formation and mixing ratios are performed by single-crystal X-ray diffraction and nuclear magnetic resonance spectroscopy analyses. By changing the mixing ratio, we achieve continuous changes in the emission lifetimes and the emission quantum yields. [ABSTRACT FROM AUTHOR]

In oleogel food systems (based on the mixture between stearic acid and stearyl alcohol) the strong effect of the weight ratio (R) between these two components on the textural and structural properties is well described. The effect of R for other fatty acids and fatty alcohols is less explored. Moreover, they do not show an enhancement of the oleogel properties for specific R. The effect of R on the oleogel properties, for a mixture of fatty acid and fatty alcohol with longer alkyl chains (behenyl alcohol and behenic acid) in sunflower and soybean oils, which are raw materials widely used in cosmetic and pharmaceutical industries, was investigated. We characterized the oleogel properties as a function of R in terms of structuring potential: hardness, oil loss and gel stability. This information was correlated with microstructural data obtained at different length scales by coupling optical microscopy, DSC, SFC, SAXS and WAXS experiments. Our results highlight that R tunes the oleogel properties in a comparable manner to previous results obtained for stearic acid and stearyl alcohol-based oleogels. Two specific R (8:2 and 7:3) close to the 3:1 molecular ratio gave oleogels with both the highest hardness and stability. The morphology and size of the mixed crystals obtained for these R cannot solely explain why they are stronger gels with low oil loss in comparison to the other R. The almost complete crystallization for these two R is one of the key parameters controlling the oleogel properties. As described in the literature, we also suggest that the differences in oleogel properties come from the spatial distribution of the crystalline mass. In this study, we confirm that the effect of the 3:1 molecular ratio in mixed surfactant systems described more than 50 years ago for foams, emulsions and Langmuir monolayers occurs also on the crystallization of mixed fatty alcohol and fatty acid in oils leading to better oleogels properties. [ABSTRACT FROM AUTHOR]

The crystals of pure [(CH3)3NH]2[KFe(CN)6] (TrMAFe) and [(CH3)3NH]2[KCo(CN)6] (TrMACo) as well as their mixed crystals (TrMAFexCo1−x), with different ratios of x = 0, 0.12, 0.18, 0.49, 0.56, 0.73, 0.81, 1.0, have been grown from aqueous solutions. The structure of TrMACo has been determined at 360 K to be cubic (Fm3¯m). In phase II (100 K), the TrMACo crystal is monoclinic (C2/c). The thermal stability of the pure and mixed crystals has been determined by using both DTA and TGA. Based on the DSC results, we have found a single phase transition (PT) for both pure and mixed crystals. The Fe(III) concentration was estimated by using the SEM technique. We have found a linear relationship between the PT temperature (Tc) and the molar concentration of Fe(III). Based on the obtained results, a phase diagram has been constructed. The mechanism of the structural PT has been discussed based on the results of dielectric relaxation and 1H NMR and X-ray spectroscopy measurements. The results confirmed that the PT mechanism of both pure and mixed crystals is related to the change in the dynamic state of the TrMA+ cations. The dielectric activation energy changes linearly with the mole fraction ranking from 35 to 38 kJ mol−1, for the mixed crystals. [ABSTRACT FROM AUTHOR]

Rutile TiO2 and binary/ternary/quaternary the TiO2–Ti2O3(H2O)2(C2O4)·H2O mixed crystal possessing self-assembled morphology and serving as catalysts for the photocatalytic degradation of organic pollutants or as photoanodes for photoelectrochemical (PEC) water splitting have been prepared by in situ growth via changing the concentration of potassium titanyl oxalate. The rutile/anatase TiO2 with mesoporous structure has a specific surface area of 27.896 m2 g−1 and an average pore size of 3.411 nm. The sample has a relatively more regular self-assembly morphology after heat-treatment at different temperatures; however, its photocatalytic activity is reduced. Excellent catalytic oxidation of methyl orange (MO) and hydroxylbenzoic acid (HBA) is observed on the as-synthesized samples, wherein rutile/anatase TiO2 and rutile/anatase/brookite TiO2–Ti2O3(H2O)2(C2O4)·H2O show excellent photocatalytic activity under UV-light. With the novel TiO2–Ti2O3(H2O)2(C2O4)·H2O mixed crystal catalyst, this study illustrates the photocatalysis mechanism of a multiphase mixed crystal for the removal of emerging contaminants in water. Based on the Mott–Schottky, XPS and energy band structure data, we consider that an indirect Z-scheme transmission mode is generated between rutile/anatase TiO2 or TiO2–Ti2O3(H2O)2(C2O4)·H2O mixed crystal, wherein the photo-induced electrons in rutile TiO2 combined with the holes in anatase TiO2 or Ti2O3(H2O)2(C2O4)·H2O, leading to enhanced charge carrier extraction and utilization upon photoexcitation. [ABSTRACT FROM AUTHOR]

An ultra‐slow crystal growth over a period of 24 h of a newly synthesized CH3NH3Pb1/2Bi1/3I3 perovskite (MPBI) nanocrystal in non‐polar toluene medium is reported here. From several spectroscopic techniques as well as from TEM analysis we found that the size of nanocrystals changes continuously with time, in spite of being capped by the ligands. Using a single molecular spectroscopic technique, we also found that this size change is not due to the stacking of nanocrystals but due to crystal growth. The notable temperature dependence and reversible nature of the nanocrystals growth is explained by the dynamic nature of the capping. The observed temperature‐dependent ultra‐slow growth is believed to be a pragmatic step towards controlling the size of perovskite NC in a systematic manner. [ABSTRACT FROM AUTHOR]

In anisotropic crystals, optical isotropic points are wavelengths where linear birefringence disappears because the refractive indices for both eigenmodes are accidentally equivalent. Here, the optical isotropic point of ethylenediammonium selenate (EDSe) is tuned by generating a solid‐solution series of EDSe doped with sulfate. Mueller matrix polarimetry and single‐crystal X‐ray diffraction are used to correlate changes in linear birefringence with the crystal composition of EDSxSe1−x. A scheme for using mixed crystals with isotropic points as tunable birefringent optical bandpass filters is proposed and their performance is modeled. [ABSTRACT FROM AUTHOR]

A mixed alkaline-earth powellite, Ca0.84Sr0.16MoO4 (calcium strontium molybdate), was synthesized by a flux method and its crystal structure was solved using single-crystal X-ray diffraction (SC-XRD) data. The compound crystallized in the I41/a space group as with a typical CaMoO4 powellite, but with larger unitcell parameters and unit-cell volume as a result of the partial incorporation of larger Sr cations into the Ca sites within the crystal. The unit cell and volume were well fitted with the trendline calculated from literature values, and the powder X-ray diffraction (P-XRD) pattern of the ground crystal is in good agreement with the calculated pattern from the solved structure. [ABSTRACT FROM AUTHOR]

A mixed alkaline-earth powellite, Ca0.84Sr0.16MoO4 (calcium strontium molybdate), was synthesized by a flux method and its crystal structure was solved using single-crystal X-ray diffraction (SC-XRD) data. The compound crystallized in the I41/a space group as with a typical CaMoO4 powellite, but with larger unitcell parameters and unit-cell volume as a result of the partial incorporation of larger Sr cations into the Ca sites within the crystal. The unit cell and volume were well fitted with the trendline calculated from literature values, and the powder X-ray diffraction (P-XRD) pattern of the ground crystal is in good agreement with the calculated pattern from the solved structure. [ABSTRACT FROM AUTHOR]

Herein, in order to determine the formation feasibility of 1,1-diamino-2,2-dinitroethylene (FOX-7)/ ammonium perchlorate (AP) mixed crystals, three configurations of FOX-7/AP composites (FOX-7/AP1, FOX-7/AP2, FOX-7/AP3) were optimised, and the structures of FOX-7/AP mixed crystals were constructed. Then the electrostatic potential, binding energy and electronic density topology of FOX-7/AP composites were calculated by using the density functional theory. Finally, the radial distribution function between H atoms and O atoms of FOX-7/AP mixtures was calculated through molecular dynamics. As demonstrated by the results, there are hydrogen bond interactions in three configurations of FOX-7/AP composites. The interaction energies of FOX-7/AP1, FOX-7/AP2 and FOX-7/AP3 are 8.396, 20.537 and 38.189 kJ▪mol−1, respectively. The order of the electron density ρ(r) at the bond critical point (BCP) of three FOX-7/AP composites is FOX7-AP3 > FOX7-AP2 > FOX7-AP1. There are apparent peaks at the range of 0.11–0.31 nm and 0.31–0.5 nm for FOX-7(10-1)/AP, FOX-7(011)/AP, FOX-7(101)/AP mixed crystals. The interaction strength of the hydrogen bond is greater than that of strong van der Waals force. Therefore, it is feasible to combine FOX-7 with AP to form mixed crystals. As the content of AP in the mixed crystal is on the rise, the oxygen balance of the system shows a gradually increasing trend. [ABSTRACT FROM AUTHOR]

A three-body interaction potential has been employed for the study of cohesive, harmonic and anharmonic elastic properties of NH4Cl-NH4Br mixed crystals. This interaction potential consists of the long-range Coulomb interactions, van der Waals (vdW) dipole-dipole and dipole-quadrupole interactions and overlap of Born Mayer repulsive potential. This model potential has succeeded in predicting the cohesive energy, thermal properties and the second order elastic (SOE) constants of the NH4Cl-NH4Br mixed crystals. [ABSTRACT FROM AUTHOR]

A von Hamos Bragg crystal spectrometer at 1C beamline of Pohang Accelerator Laboratory for x-ray emission spectroscopy (XES) is described. Diced Si crystals of different orientations ([111], [110], [100], and [311]) are glued onto a planoconcave glass substrate having 250/500 mm radius of curvature. To enhance the spectrometer efficiency, the length of the crystal analyzer is kept 200 mm. The emission spectra of Cu foil and Fe foil and elastic scattering from Al foil are measured using the von Hamos geometry in which curved crystals disperse the x-rays. Spectrometer efficiency and energy resolution are measured at various x-ray photon energies. X-rays are incident at 6.54 keV, 9.00 keV, 9.205 keV, and 11.51 keV for Si(440), Si(444), Si(800), and Si(933) crystal analyzers, respectively. The cylindrical figured analyzer is placed near 80° with respect to the sample, which gives better energy resolution. The spectrometer efficiency of the Si(444) crystal analyzer increases by ∼2 times when the length of the analyzer is increased from 100 mm to 200 mm. Furthermore, to measure Fe Kα1, Kα2, and Kβ simultaneously, we made a mixed crystal analyzer in which alternative strips of Si[111] and Si[110] are glued onto one preshaped cylindrical substrate. The enhanced efficiency and simultaneous measurement of Kα and Kβ emission lines will give an edge over in situ and time-resolved x-ray emission spectroscopy studies. The information extracted with a high efficiency spectrometer from low intensity XES emission lines will be useful for the in situ elemental characterization in catalytic reactions. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate for the first time a doubly Q-switched pulsed laser, using a novel Nd:Gd0.69Y0.3NbO4 mixed crystal and acousto-optical (AO) Q-switch and Cr4+:YAG saturable absorber. Compared to purely AO Q-switched lasers, the simultaneous use of AO Q-switches and Cr4+:YAG saturable absorbers provides the generation of a shorter pulse. We investigated in detail the output characteristics of pulsed Nd:Gd0.69Y0.3NbO4 lasers. [ABSTRACT FROM AUTHOR]

TiO2 has been widely accepted in various photocatalysts due to its low cost, high stability, structural robustness and non-toxicity. Hydrothermal method was used to prepare TiO2 photocatalysts with different morphology, structure and crystal morphology, including three-dimensional TiO2 spheres, shuttle-shaped TiO2, one-dimensional nanorod TiO2 and nanotube TiO2 films. The photocatalytic degradation of methylene blue by titanium dioxide with five different morphologies under white light was characterized by scanning electron microscope, X-ray diffraction, fourier transform infrared spectroscopy and ultraviolet visible light absorption spectroscopy, and the effects of morphology, structure and crystal type on TiO2 performance were analyzed. The preparation methods of titanium dioxide photocatalyst with good properties were compared. It is proven that higher crystallinity, small particle size, larger specific surface area, higher absorbance and a certain proportion of mixed crystal phase are beneficial to obtain better photocatalytic performance. [ABSTRACT FROM AUTHOR]

The impact of formulation variables on the optimization of pilot scale clobetasol 17-propionate (CP) cream formulations was investigated using a Central Composite Design of Experiments. Thirty batches of cream were manufactured and the formulation variables assessed were % v/v propylene glycol, % w/w Gelot® 64, cetostearyl alcohol and glyceryl monostearate content. The responses monitored included viscosity, spreadability, pH, CP content, extrudability, electrical conductivity, and % CP released at 72 hours. The responses were compared to those of a reference product, Dermovate® cream. ANOVA analysis revealed that viscosity, spreadability, and % CP released at 72 hours were significant formulation responses (p < 0.05). Cetostearyl alcohol had the greatest impact on quality of pilot scale products. An increase in cetostearyl alcohol resulted in an increase in viscosity, a decrease in spreadability, and a decrease in % CP released at 72 hours. The optimized pilot scale CP formulation contained 46% v/v propylene glycol, 8.6% w/w cetostearyl alcohol, 10.5% w/w glyceryl monostearate, and 3.8% w/w Gelot® 64. The resultant viscosity, spreadability, pH, CP content, extrudability, electrical conductivity, and % CP released were 44633cP, 24.91cm2, 101.23 %, 76.98 g/cm2, 198.23 µS/cm, and 50.23%. The addition of cetostearyl alcohol and Gelot® 64 is critical for establishing a soft formulation that leads to the formation of a mixed crystal bilayer network of high viscosity. The formation of a separate crystalline lipophilic network usually occurs in semi-solid formulations that contain high concentrations of emulsifier, leading to an increase in shear stress and greater physicochemical stability of the formulation. The use of experimental design approaches to formulation development activities, permit evaluation of multiple factors simultaneously, reducing the time and costs asscoiated with product development activities, whilst identifying a composition design space and ensuring stable and effective dosage forms are produced. [ABSTRACT FROM AUTHOR]

Microhardness of (Cu1-xAgx)7GeSe5I mixed crystals and composites on their base was investigated using the Vickers indenter at room temperature. (Cu1-xAgx)7GeSe5I mixed crystals were obtained using the Bridgman-Stockbarger method. Composites on their base were prepared as a pressed mixture of (Cu1-xAgx)7GeSe5I micropowder and ethylene-vinyl acetate polymer in 90:10 concentration ratio, respectively. Dependences of microhardness versus the indenter penetration depth have been analyzed. Influence of Cu+Ag+ isovalent cation substitution on the microhardness of (Cu1-xAgx)7GeSe5I mixed crystals and composites on their base have been studied. [ABSTRACT FROM AUTHOR]

Bulk-rock compositions are commonly used as proxies for melt compositions, particularly in silicic plutonic systems. However, crystal accumulation and/or melt loss may play an important role in bulk-rock compositional variability (McCarthy and Hasty 1976; McCarthy and Groves 1979; Wiebe 1993; Wiebe et al. 2002; Collins et al. 2006; Deering and Bachmann 2010; Miller et al. 2011; Vernon and Collins 2011; Lee and Morton 2015; Lee et al. 2015; Barnes et al. 2016a; Schaen et al. 2018). Recognizing and quantifying the effects of crystal accumulation and melt loss in these silicic systems is challenging. Hornblende-melt Fe/Mg partitioning relationships and hornblende (Hbl) chemometry are used here to test for equilibrium with encompassing bulk-rock and/or glass compositions from several plutonic and volcanic systems. Furthermore, we assess the extent to which these tests can be appropriately applied to Hbl from plutonic systems by investigating whether Hbl from the long-lived (~10 Ma) Tuolumne Intrusive Complex preserves magmatic crystallization histories. On the basis of regular zoning patterns, co-variation of both fast- and slow-diffusing trace elements, Hbl thermometry, and compositional overlap with volcanic Hbl we conclude that Hbl from plutons largely preserve records supporting the preservation of a magmatic crystallization history, although many compositional analyses yield calculated temperatures <750 °C, which is unusual in volcanic Hbl. Hornblende is only rarely in equilibrium with host plutonic bulk-rock compositions over a wide range of SiO2 contents (42–78 wt%). Hornblende chemometry indicates that the majority of Hbl from the plutonic systems investigated here is in equilibrium with melts that are typically more silicic (dacitic to rhyolitic in composition) than bulk-rock compositions. These results are consistent with crystal accumulation and/or loss of silicic melts within middle- to upper-crustal plutons. Although the processes by which melts are removed from these plutonic systems is uncertain, it is evident that these melts are either redistributed in the crust (e.g., leucogranite dikes, plutonic roofs, etc.) or are instead erupted. In contrast, Hbl from volcanic rocks is more commonly in equilibrium with bulk-rock and glass compositions. In most cases, where Hbl is out of equilibrium with its host glass, the glasses are more evolved than the calculated melts indicating crystallization from a less fractionated melt and/or mixed crystal populations. Where Hbl is not in equilibrium with volcanic bulk-rocks, the bulk-rock compositions are typically more mafic than the calculated melts. In some intermediate volcanic samples, the occurrence of wide-ranges of calculated melt compositions is indicative of magma mixing. The general absence of Hbl with temperatures <750 °C from volcanic systems suggests that magmatic mushes below this temperature are unlikely to erupt. Our results indicate that bulk-rock compositions of granitic plutonic rocks only rarely approximate melt compositions and that the possibility of crystal accumulation and/ or melt loss cannot be ignored. We suggest that detailed assessments of crystal accumulation and melt loss processes in magmatic systems are crucial to evaluating magma differentiation processes and discerning petrogenetic links between plutonic and volcanic systems. [ABSTRACT FROM AUTHOR]

The evolution of the primary relaxation time of orientationally disordered (OD) mixed crystals [(CH3)2C(CH2OH)2]1-X[(CH3)C(CH2OH)3]X, with 0≤X≤0.5, on approaching the glass temperature (Tg) is discussed. The application of the distortion-sensitive, derivative-based procedure revealed a limited adequacy of the Vogel–Fulcher–Tammann parametrization and a superiority of the critical-like description τ∝(T-TC)-[lowercase_phi_synonym]′, [lowercase_phi_synonym]′=9–11.5, and TC∼Tg-10 K. Basing on these results as well as that of Drozd-Rzoska et al. [J. Chem. Phys. 129, 184509 (2008)] the question arises whether such behavior may be suggested as the optimal universal pattern for dynamics in vitrifying OD crystals (plastic crystals). The obtained behavior is in fair agreement with the dynamic scaling model (DSM) [R. H. Colby, Phys. Rev. E 61, 1783 (2000)], originally proposed for vitrifying molecular liquids and polymers. The application of DSM made it possible to estimate the size of the cooperatively rearranging regions (“heterogeneities”) in OD phases near Tg. [ABSTRACT FROM AUTHOR]

We present studies of magnetic and transport properties of Ge1-x-ySnxMnyTe mixed crystals with chemical compositions 0.083¿x¿0.142 and 0.012¿y¿0.119. The transport characterization measurements were performed at temperatures 4.2<300 K. The results showed feature characteristic for narrow gap semiconductors, e.g., metallic conductivity with pxx¿10-4 ¿ cm and hole concentrations p>1021 cm-3. It was found that the transport properties strongly depend on the chemical composition of the alloy. The magnetic investigations included measurements of linear ¿1 and harmonic ¿2,3 ac susceptibilities as a function of temperature and of the applied magnetic field amplitude and frequency. Qualitative analysis of our experimental data showed that in the studied system, in the investigated composition range, the spin glass order exists at temperatures up to 50 K. [ABSTRACT FROM AUTHOR]

Analysis of the optical properties of bulk Cu(In1-xGax)3Se5 mixed crystals synthesized from the elements as a function of the Ga content is presented. Measurements of the complex dielectric function [variant_greek_epsilon](ω)=[variant_greek_epsilon]1(ω)+i[variant_greek_epsilon]2(ω) were performed at room temperature in the photon energy range of 0.8–4.7 eV using a variable angle of incidence ellipsometer. The spectral dependence of the complex refractive index, the absorption coefficient, and the normal-incidence reflectivity were also derived. The structure observed in the dielectric functions attributed to the interband transitions E0, E1A, and E1B has been modeled using a modification of the Adachi’s model. The results are in excellent agreement with the experimental data over the entire range of photon energies. The model parameters, including the energies corresponding to the lowest direct gap and higher critical points, have been determined using the simulated annealing algorithm. The values of E0 and E1A are found to increase linearly with the increasing Ga content. [ABSTRACT FROM AUTHOR]

We report a detailed investigation of the temperature dependence of the band-edge excitonic transitions of three Zn1-x-yBexMgySe mixed crystals using contactless electroreflectance (CER) and photoreflectance (PR) in the temperature range of 15–400 K. The samples were grown by the modified high pressure Bridgman methods. The fundamental transition energy E0 and broadening parameters are determined via a lineshape function fit to the CER and PR spectra. The parameters that describe the temperature dependence of the band-edge excitonic transition energy and broadening parameters are evaluated and discussed. [ABSTRACT FROM AUTHOR]

A detailed optical characterization of Zn0.96Be0.04Se and Zn0.93Mg0.07Se mixed crystal samples grown by the modified high-pressure Bridgman method has been carried out via photoluminescence (PL), contactless electroreflectance (CER), and photoreflectance (PR) in the temperature range of 15–400 K. With these optical diagnostic tools we observed features originating from exciton emission, an edge emission due to recombination of shallow donor-acceptor pairs (DAPs), and a broad band related to recombination through deep-level defects, as well as band-edge and spin-orbit splitting critical points interband transitions in CER and PR experiments. The optical properties of these two mixed crystals are compared. Our comparative study revealed that the beneficial effect of beryllium (Be) incorporation is superior to that of magnesium (Mg), in the sense that a Be-containing ternary alloy resulted in better crystalline quality with more intense excitonic emission line and weaker DAPs and deep-level defect-related bands. The peak positions of the excitonic emission lines in the PL spectra correspond quite well to the energies of the fundamental transitions obtained by means of electromodulation spectra. The parameters that describe the temperature dependence of the fundamental and spin split-off band gaps, and the broadening function of the band-edge excitons, are evaluated and discussed. [ABSTRACT FROM AUTHOR]

A detailed optical characterization of a series of wurtzite-type Cd1-x-yBexZnySe mixed crystals grown by the modified high pressure Bridgman method has been carried out via photoluminescence (PL) and contactless electroreflectance (CER) in the temperature range of 15–300 K. Room temperature surface photovoltage spectroscopy has been used as a diagnostic technique for checking the surface condition of the sample. For the mechanically polished sample, the surface photovoltage spectrum at room temperature recorded a below band edge broad feature which is most likely related to the surface states induced by mechanical defect. This feature can be eliminated via mechanical polishing and followed by chemical etching, and hence, only the exciton line was observed for the damage-removed sample. Typical PL spectrum at low temperature consists of an exciton line, an edge emission due to recombination of shallow donor-acceptor pairs, and a broadband related to recombination through deep level defects. Various interband transitions, originating from the band edge and spin-orbit splitting critical points, of the samples have been observed in the CER spectra. Comparison of PL and CER data for the Cd1-x-yBexZnySe samples shows that for a low Zn and Be content the peak positions of the excitonic emission lines in the PL spectra correspond quite well to the transition energies of the A exciton from the CER data. For samples with higher Be and Zn contents, the results indicate that localization of excitons has taken place at low temperatures. The parameters that describe the temperature dependence of the transition energy and broadening parameter of the fundamental band edge exciton have been evaluated and discussed. [ABSTRACT FROM AUTHOR]

• DNA tiles were annealed and assembled into porous crystals by optimized sitting drop growth conditions. • DNA crystal-lanthanide complexes hybrid materials were synthesized. • Curcumin can quench the fluorescence of hybrid luminescent crystals. • Glutathione can change the fluorescence color of hybrid luminescent crystals. In this study, a highly sensitive anticancer drug sensor was synthesized using DNA crystals loaded with luminescent Ln3+(Eu3+/Tb3+) complexes. The sensors exhibited a pronounced color transformation property due to the differential quenching of Eu3+ and Tb3+ emissions upon drug interactions. These luminescent hybrid DNA crystals present a significant advancement in sensing anticancer drugs like curcumin, transitioning from monitoring fluorescence intensity changes to a visually discernable color change. This new approach eliminates the need for specialized instrumentation. Owing to the intrinsic biocompatibility of materials composed of DNA, this hybrid sensor has the potential to sense drugs within the human body. Hybrid crystals loaded with a single complex will lose their fluorescence properties due to drug quenching; however, crystals loaded with mixed complexes emit distinct fluorescent colors, such as yellow-green and orange-red, at different drug concentrations. This color transformation allows for the direct determination of drug concentration based on crystal color, making the sensing process more simple and easily observable. [ABSTRACT FROM AUTHOR]

• A mixed failure mode of slip and cleavage for FCC single crystals is studied. • A novel thermodynamics-based damage evolution model is proposed. • The slip-dominant fracture of a single crystal copper is investigated. • The cleavage-dominant fracture of a nickel-based single crystal alloy is predicted. • The competition effect between slip damage and cleavage damage is revealed. In this study, a microdamage model is newly proposed to predict the failure process of FCC single crystals. Two micro damage mechanisms, slip and cleavage, are both involved in the model. A microscopic damage variable is first defined at the slip plane scale, and a damage coupled crystal plasticity constitutive equation in a co-rotational tensor framework is then established. A damage driving force consisting of generalized energies related to the resolved shear stress and the positive resolved normal stress is proposed to reflect the mixed failure mechanism of FCC single crystals induced by slip and cleavage. The damage evolution equation is then derived in the framework of thermodynamics. An explicit algorithm for the damage coupled crystal plasticity finite element method is given. The proposed microdamage model is utilized to predict the slip-dominant fracture behavior of a single crystal copper and the cleavage-dominant fracture behavior of a nickel-based single crystal alloy. The damage evolution process of slip planes is given and the influence mechanism is revealed. The calculated results agree well with the experimental data, which verifies the good capability of the proposed model in describing and predicting the multi failure processes of FCC metals. Finally, a 2D fracture simulation of a single crystal notched specimen under shear loading is conducted, and the effect of damage parameters on the fracture modes is also discussed. [ABSTRACT FROM AUTHOR]

The conditions of phase formation in the ternary water-salt system comprised of NiSO 4 –CoSO 4 –H 2 O at 25 °C, which is the first step for the creation of structurally perfect mixed crystals Co x Ni (2–x) (SO 4) 2 ·12H 2 O, have been studied. The crystallization regions of tetragonal NiSO 4 ·6H 2 O in the NiSO 4 :CoSO 4 ratio range from 100:0 to 95:5 mass% and monoclinic solid solution of Co x Ni (2–x) (SO 4) 2 ·12H 2 O in the NiSO 4 :CoSO 4 ratio range from 95:5 to 0:100 mass% were delineated. A set of Co x Ni (2–x) (SO 4) 2 ·12H 2 O single crystals in the range of 0.05 ≤ x ≤ 1.95 was obtained. The crystal structures of the samples with x values equal to 1.5, 1.13, and 0.56 have been studied. The Co x Ni (2–x) (SO 4) 2 ·12H 2 O crystals are a series of solid solutions based on the crystal structure of CoSO 4 ·6H 2 O. The transmission spectra in the λ range of 200–800 nm were studied for the obtained crystal samples. A significant decrease in the intensity of the transmission bands in the visible region of the spectrum was observed due to the simultaneous presence of [Ni(H 2 O) 6 ] and [Co(H 2 O) 6 ] complex octahedra in the crystal structures. Consequently, the Co x Ni (2–x) (SO 4) 2 ·12H 2 O crystals are a promising material for optical filters used in photonics. • The conditions of phase formation in system NiSO 4 –CoSO 4 – H 2 O at 25 °C are considered. • A set of Co x Ni (2-x) (SO 4) 2 ·12H 2 O single crystals in the range 0.05 ≤ x ≤ 1.95 was obtained. • The crystal structure of Co x Ni (2-x) (SO 4) 2 ·12H 2 O has been studied. • A transmission spectra was studied for Co x Ni (2-x) (SO 4) 2 ·12H 2 O crystal samples. • Shown the Co x Ni (2-x) (SO 4) 2 ·12H 2 O crystals are a promising material for optical filters which used in photonics. [ABSTRACT FROM AUTHOR]

A new mixed orthophosphate crystal of Nd3+:LuYPO 4 was grown by high temperature solution method successfully. The optical properties including polarized absorption and emission spectra as well as the fluorescence decay curve have been investigated in detail. The calculated absorption cross-sections were 18.6 × 10−20 cm2 at 803 nm with a FWHM of 6.10 nm for π-polarization and 8.96 × 10−20 cm2 at 804 nm with a FWHM of 6.07 nm for σ-polarization, respectively. The broad absorption bands wider than those of Nd:YPO 4 and Nd:LuPO 4 crystals confirm that the incorporation of Lu3+ ions results in a effectively inhomogeneous broadening of the spectra. Based on J-O theory, some typical parameters such as J-O intensity, fluorescence branching rate and radiation lifetime of Nd3+ ions in Nd:LuYPO 4 crystal were systematically calculated. Besides, five strong emission peaks located at 1054, 1061, 1066, 1076 and 1081 nm can be observed obviously from fluorescence spectra. All the results show that Nd:LuYPO 4 crystal is a promising laser material applied to 1.0 μm with multi-wavelength emission characteristics. [Display omitted] • The Nd3+:LuYPO 4 crystal was grown successfully from Pb 2 P 2 O 7 solution. • An effectively inhomogeneous broadening of the spectra at around 808 nm for Nd3+:LuYPO 4 crystal. • Spectral parameters of Nd3+ ions were calculated in detail based on J-O theory. [ABSTRACT FROM AUTHOR]

Prulifloxacin, a broad-spectrum quinolone antibiotic, exhibits three distinct crystal forms, each with different bioavailability and therapeutic properties. It is imperative to assess and control the proportion of each crystal form during the production of raw materials and preparations. Therefore, it is necessary to establish an analytical method that can determine the content of each crystal form in the ternary polycrystalline mixtures. In this study, prulifloxacin crystal forms were analyzed and quantitatively measured using Raman spectroscopy. First, three pure crystal forms of prulifloxacin were prepared under different crystallization conditions and mixed into ternary mixtures at the designed proportions. Subsequently, the ternary mixed crystal samples were analyzed using a Raman microscope.Then run a partial least squares regression analysis to establish a PLS quantitative model using the average spectra data, and a non-negative least squares analysis to establish an area percentage quantitative model using Raman imaging data.The method validation results showed that the two models successfully predicted the proportion of each crystal form within the prulifloxacin polycrystalline mixtures, with a prediction accuracy of less than ± 10 %. Raman spectroscopy was thus established as an effective method for crystal form analysis and quantitative measurement of prulifloxacin. [Display omitted] • Studied the percentage of each crystal form of prulifloxacin by Raman technology. • Established a PLS quantitative model using Raman spectra. • Established an area percentage quantitative model using Raman imaging maps. • The method validation results showed that both models were precise and accurate. [ABSTRACT FROM AUTHOR]

Here we present the study of spectral and kinetic characteristics of Er3+ ions in the heavily doped BaY 1.8 Lu 0.2 F 8 mixed crystals, which are homologous to well-known fluoride host BaY 2 F 8 with high value of crystal field splitting. Absorption and luminescence spectra were registered, and the luminescence decay was studied in the IR spectral range for BaY 1.8 Lu 0.2 F 8 crystals doped with Er3+ ions at concentrations of 20.0 at. % and 30.0 at. %. Based on the Judd-Ofelt theory, the intensity parameters were determined from the absorption spectra with the use of two approaches, the standard theory (J-O), and the intermediate configuration interaction (ICI). It is shown that investigated BaY 1.8 Lu 0.2 F 8 :Er3+ crystals propose the value of stimulated emission cross-section at the wavelength around 2.7 μm higher than that for Er-doped YAG and at the level of Er-doped LiYF 4 crystals. In addition, it was shown that for BaY 1.8 Lu 0.2 F 8 crystals with a high doping level of Er3+ (more than 20.0 at. %), the radiative lifetime of the 4I 13/2 state becomes shorter than the lifetime of the 4I 11/2 state, which speaks for success on efficient laser oscillation at a wavelength of about 2.7 μm (the 4I 11/2 → 4I 13/2 transition). • Stimulated emission cross-section around 2700 nm is higher in BaY 1.8 Lu 0.2 F 8 :Er than in YAG:Er and at the level of LiYF 4 :Er. • Lu3+ doping led to larger total spectral width of 4I 11/2. → 4I 15/2 and 4I 11/2 → 4I 13/2 transitions in BaY 1.8 Lu 0.2 F 8 :Er crystals compared to Er:LiYF 4 • Lifetime of 4I 13/2 becomes shorter than 4I 11/2 in BaY 1.8 Lu 0.2 F 8 with a high doping level of Er3+ (more than 20 %). • The Judd-Ofelt analysis for BaY 1.8 Lu 0.2 F 8 :Er with the ICI approach agreed better with experimental data. [ABSTRACT FROM AUTHOR]

K2NiXCo(1−X) (SO4)2·6H2O (KCNSH) mixed crystal is a promising material for solar blind optical filters, combining high transparency in the ultraviolet range with effective suppression of the visible spectral region. Increasing the mechanical strength of these crystals is important to enable them to be machined in the manufacture of optical elements. A comprehensive study of the inhomogeneities and crack resistance of KCNSH crystal as a function of the growth conditions was carried out. The influence of the radial and mosaic inhomogeneity, as well as other structural defects, on the crack resistance of the crystals was analyzed. To assess the crack resistance of crystals, the parameters ca (crack length), c/a (the ratio of crack length to the size of the indentation), and KC (fracture toughness) were used. The correctness of the obtained results was analyzed. The conditions for growing KCNSH crystals with the best crack resistance were determined on the basis of the results of the study. It is shown that growing the mixed crystals using the temperature difference technique with a peripheral solution supply into the shaper provides the best crystal quality.

The mosaic and radial inhomogeneity of shaped mixed crystals of K2NixCo(1–x)(SO4)2·6H2O (KCNSH) were studied depending on the supercooling of solution, its velocity and its method of supply into the shaper. It was shown that mosaic inhomogeneity could be suppressed when solution is supercooled to about 2 °C. Peripheral supply of the solution (tangential to the wall of the shaper to create a “swirling” flow) with a rate of 55–135 cm/s provides better composition uniformity along the crystal surface in comparison with upright supply of the solution (flow is perpendicular to the crystal surface).