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The susceptibility of either oxidation into Sn(IV) or disproportionation into Sn(IV) and Sn(0) limits the study of metal tin‐(II)‐borate ceramics. We report mullite‐type SnCrBO4 and SnVBO4 synthesized in sealed quartz tubes by conventional solid‐state method. X‐ray powder diffraction data Rietveld refinements confirm that both compounds are isostructural to PbMBO4 phases for M = Al, Ga, Cr, Mn, and Fe. The end‐members show a complete miscibility within the Sn(Cr1−xVx)BO4 solid solution. Both the microstructural (average crystallite size, microstrain, and degree of crystallinity) and crystal structural (metric parameters, bond lengths, polyhedral volume, and polyhedral distortion) parameters are observed with respect to the compositional x‐value. The stereochemical activity of the 5 s2 lone electron pairs of Sn2+ cations has been measured by using the Wang–Liebau eccentricity parameter. The structural features are complemented by 119Sn Mössbauer, Raman, and Fourier‐transformed infrared spectroscopy. The 119Sn Mössbauer isomer shifts and the quadrupole splitting values confirm the SnO4 coordination and an Sn(II) valence state. The electronic band gap has been calculated from the UV/Vis diffuse reflectance spectra, which slightly increases with successive decrease of the cationic radius from V to Cr. Temperature‐dependent inverse DC magnetic susceptibility suggests that SnCrBO4 and SnVBO4 are antiferromagnetic and ferromagnetic (FM) with a Néel temperature of 17.2(1) K and a Curie temperature of 29.8(1) K, respectively. Alike the end‐member SnVBO4, Sn(Cr0.5V0.5)BO4 is also found to be a rare FM insulator. The thermal stability decreases with increasing vanadium content in the solid solution. [ABSTRACT FROM AUTHOR]

Two azo dye ligands, bearing different substituents (chlorine atom or methoxy group) in the para‐position of the phenyl ring, were employed for the synthesis of two Cu(II) chelates. Full structural affirmation of complexes was assessed. X‐ray diffraction measurements revealed that the coordination geometry for Cu atoms in both complexes is square‐pyramidal with a ligand:metal ratio of 2:1 where dyes behave as monobasic bidentate ligands. Thermogravimetric analyses of the complexes and their starting dyes were performed to study their thermal stabilities and decomposition behavior confirming the thermal stability of both dyes and complexes. Antioxidative activity of the complexes has been assigned and compared with their parent ligands revealing that the presence of the electron–donor, methoxy group, in the phenyl ring, in both dye and complex, is responsible for the activity (IC50 values of 1.54 for the dye and 1.30 mM for the complex). It should be stated that the complexation of the methoxy‐substituted dye leads to enhanced antioxidative activity concurrent to a standard antioxidant molecule of ascorbic acid, making this molecule a promising antioxidant agent. Docking study with vascular endothelial growth factor receptor 2 and Aurora kinase A proteins indicate that complexes exhibit higher binding affinities to proteins than the starting ligand dyes. The most promising structure exhibiting the best docking potential toward both proteins is the complex‐bearing methoxy group. The presented results represent a promising start for further investigations of these compounds as potential therapeutic candidates for the treatment of various types of cancer. [ABSTRACT FROM AUTHOR]

Four compounds with the composition Cd(NCSe)2(3‐ClPy)4 (1), [Cd(NCSe)2(3‐ClPy)2] ⋅ 3‐ClPy (2), Cd(NCSe)2(3‐ClPy)2 (3) and Cd(NCSe)2(3‐ClPy) (4) with 3‐ClPy = 3‐chloropyridine were synthesized. In the structure of 1 discrete complexes are observed, whereas in 2 the Cd cations are linked by pairs of selenocyanato anions into chains and between the chains 3‐chloropyridine solvate molecules are embedded. In compound 3 each two Cd cations are linked by pairs of anionic ligands into dinuclear units, that are further connected into layers by μ‐1,3 single bridging selenocyanate anions. In compound 4, both, octahedrally and tetrahe‐ drally coordinated Cd cations are present, that are linked by μ‐1,3‐ bridging anionic ligands into a three‐.dimensional network. Thermoanalytical investigations prove that compound 1 loses the 3‐chloropyridine ligands stepwise upon heating and transforms into compound 4via compound 3 as an intermediate. Further investigations show that the thiocyanate analogue Cd(NCS)2(3‐ClPy) 5 that is not reported in the literature can also be prepared. Since no single crystals were available, the structure was solved from PXRD data and refined using the Rietveld method, which revealed that this compound is an isomer of 4. In its crystal structure the Cd cations are linked by μ‐1,3(N,S) and μ‐1,3,3(N,S,S)‐bridging anionic ligands into chains that are further connected via Cd2S2 rings into double chains. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the effects of pressure on starch properties were summarised and discussed. Firstly, high pressure can decrease the relative crystallinity of starch. After a 600 MPa treatment for 10–30 min, the relative crystallinity is reduced by about 37.1% on average. Meanwhile, high pressure can transform the A‐type or C‐type crystal into B‐type crystal. The destruction of high‐pressure treatment to starch crystalline structure is mainly achieved by disturbing the regular arrangement of double‐helixes, instead of directly destroying the double‐helix structure. Secondly, high pressure showed different effect trends on pasting and thermal properties of different starches. In most cases, the enthalpy of starch would become 0 after a 600 MPa treatment for 10–30 min. Thirdly, high pressure can increase retrogradation rate by 1.12–1.81 times. Fourthly, high‐pressure treatment increases the G′, G′′, apparent viscosity and yield stress of starch gel, and has different effect trends on flow behaviour index and consistency coefficient of different starches. Fifthly, high pressure can increase the RS content, up to 466.7%. This paper can provide reference for the application of high‐pressure technology in starch processing and modification. [ABSTRACT FROM AUTHOR]

Rare‐earth (RE) hafnates are promising thermal and environmental barrier coating (TEBC) materials for SiCf/SiC ceramic matrix composites. In this study, pure‐phase and dense δ‐RE4Hf3O12 (RE = Yb, Lu) bulk ceramics have been fabricated via a hot‐pressing method. The crystal structure, microstructure, mechanical, and thermal properties of δ‐RE4Hf3O12 were systematically investigated in order to probe their potential application as TEBCs. The high‐temperature elastic moduli of δ‐Yb4Hf3O12 and δ‐Lu4Hf3O12 are measured to be 185 and 188 GPa at 1673 K, respectively, which are over 85% values of room temperature. The coefficients of thermal expansion are 7.64 × 10−6 and 7.46 × 10−6 K−1 for δ‐Yb4Hf3O12 and δ‐Lu4Hf3O12, respectively. The relatively low coefficient of thermal expansion and thermal conductivity as well as their excellent high‐temperature stability endow these hafnates as potential TEBC candidates. [ABSTRACT FROM AUTHOR]

Borosulfates are an expanding class of silicate‐analogous materials. We report the syntheses and crystal structures of two unconventional cadmium borosulfates. Cd[B2O(SO4)3] crystallises in a new structure type in space group Pnma (no. 62, a=896.92(8), b=1152.0(1), c=872.75(8) pm, 1380 refl. 94 ref. param. wR2=0.112). Cd4[B2O(SO4)6] adapts the α‐Mg4[B2O(SO4)6]‐type structure with space group P3‾ ${\overline{3}}$ (no. 147, a=822.22(4), c=797.88(5) pm, 1810 refl. 58 ref. param. wR2=0.078). Together with simultaneously elsewhere reported conventional phyllosilicate‐analogous Cd[B2(SO4)4], there are now in total three cadmium borosulfates with differing dimensionality of their anions, i. e. 0D, 1D and 2D. These results highlight the special position of cadmium in the periodic table and the ambiguity of its behaviour as main group or transition metal when comparing to other analogous or related borosulfates. The [B2O(SO4)3]2− and [B2O(SO4)6]8− anions are known from other main group and transition metal borosulfates. However, Cd2+ is the first cation for which borosulfates comprising both anions are reported for the same cation. Moreover, the optical and thermal properties of both compounds are reported using IR and UV‐Vis spectroscopy as well as thermogravimetry. Both unconventional borosulfates were prepared by the thermal decomposition of the conventional borosulfate Cd[B2(SO4)4] pursueing our studies on the complex thermal decomposition behaviour of such borosulfates. [ABSTRACT FROM AUTHOR]

A novel, high‐entropy, perovskite‐structured, solid solution La(Fe0.2Co0.2Ni0.2Cr0.2Mn0.2)O3 ceramic was successfully synthesized via high‐temperature solid‐state reaction. The crystal structure, microstructure, infrared emissivity, and thermophysical properties were investigated. The experimental results indicated that La(Fe0.2Co0.2Ni0.2Cr0.2Mn0.2)O3 exhibited an infrared emissivity as high as.92 in the near‐infrared region of.76–2.50 μm. The thermal conductivity was 1.38–1.72 W m−1 K−1 in the temperature range of 25–1200°C. [ABSTRACT FROM AUTHOR]

Herein, the crystal structure, surface morphology, and magnetic and thermal properties of the BaFe11.9In0.1O19‐substituted M‐type hexaferrite are investigated. This solid solution is fabricated using "two‐step" topotactic reactions. It is determined through the X‐ray diffraction method that the crystal structure of this solid solution under normal conditions has hexagonal symmetry with P63/mmc space group (No. 194) with the unit cell parameters a = 5.8992(1) Å and c = 23.2275(7) Å. It is determined by the scanning electron microscope (SEM) researches that the average size of the grains is d¯ = 6 μm. It is determined by the vibration magnetometry that the ferrimagnet–paramagnet phase transition happens at around TC = 420 °C. Using differential scanning calorimetry (DSC), it is found that air and water molecules leave the sample surface up to 420 °C and the resulting oxygen anions appearing as a result of a solvothermal reaction fill the oxygen vacancies in the crystal structure at high temperatures up to 800 °C. The thermal transitions repeated in the high temperatures are established. The oxidation behavior of this compound is determined from thermogravimetric analysis (TGA) in a wide temperature range. [ABSTRACT FROM AUTHOR]

The complexes [Co(NH3)6][Ir(C2O4)3] and [Ir(NH3)6][Co(C2O4)3].H2O have previously been synthesized and their thermal properties studied. The [Ir(NH3)6][Ir(C2O4)3] and [Co(NH3)6][Co(C2O4)3].3H2O complexes considered here are the end members in a series of possible isostructural solid solutions based on the complex salts in the Co-Ir system. Their crystal structures and thermal properties are described in detail, including temperature-dependent in situ X-ray diffraction. During the thermolysis of these compounds, layered metal nanoparticles are formed. Close attention is paid to the details of the [Co(NH3)6][Ir(C2O4)3] synthesis. It has been shown that the formation of this complex salt is temperature dependent; upon heating, a new phase of the K3[Co(NH3)6][Ir(C2O4)3]2.6H2O salt is formed, which incorporates the initial iridium compound into the crystal structure of the double complex salt. The target [Co(NH3)6][Ir(C2O4)3] product is obtained if the synthesis is carried out at room temperature. [ABSTRACT FROM AUTHOR]

The reaction of Mn(NCS)2 with 3‐cyanopyridine in water accidentally leads to the formation of single crystals of Mn(NCS)2(H2O)2 (1). If the synthesis is performed without 3‐cyanopyridine, the known tetrahydrate Mn(NCS)2(H2O)4 is formed. In the crystal structure of the new hydrate, the Mn2+ cations are linked by pairs of μ‐1,3‐bridging anionic ligands to chains, which are further connected via Mn(NCS)2(H2O)4 units into layers, that are additionally stabilized by intralayer hydrogen bonding. These layers are linked by interlayer hydrogen bonding into a 3D network. The structure of 1 shows strong similarities to that of both the tetrahydrate and of Mn(NCS)2. The synthesis from water always leads to the tetrahydrate, which is also obtained, when Mn(NCS)2 is stored in a humid atmosphere. Thermoanalytical measurements on the tetrahydrate show a more complicated behavior, which includes melting at about 46 °C and on cooling sometimes the dihydrate is observed. If the tetrahydrate is stored in vacuum at room temperature, the dihydrate forms before the transformation to the anhydrate is observed. Isothermic water sorption measurements prove, that at low humidity the dihydrate is obtained, which transforms into the tetrahydrate at higher humidities. [ABSTRACT FROM AUTHOR]

Phase‐pure BaSnS2, with space group P21/c, is synthesized, and the structural and physical properties are investigated. Thermal properties and optical measurements are reported for the first time. The Debye temperature and Sommerfeld coefficient are obtained from temperature‐dependent heat capacity measurements, the latter indicating that BaSnS2 is an electrical insulator. A direct bandgap of 2.4 eV is obtained from diffuse reflectance and photoluminescence spectroscopy. The findings herein lay the foundation for understanding the physical properties of this material and are part of a continuing effort to investigate previously unexplored ternary chalcogenides. [ABSTRACT FROM AUTHOR]

Starch from different sources (wheat, rice, corn, waxy corn, potato, sweet potato, and kidney bean) are subjected to high pressure treatment (HPT) at 300 and 600 MPa and are evaluated for changes in digestibility, structural, thermal, and pasting properties. HPT alters the surface of starch granules and significantly disrupts morphology of granules. Increase in average granule size and decrease in relative crystallinity is observed in high pressure treated starches. However, a significant decrease average granule size is observed at 600 MPa. High pressure treated starches show progressive reduction in both swelling power and solubility with increase in pressure. HPT results in reduction in gelatinization temperatures and enthalpy of gelatinization (ΔHgel) while starches except potato starch treated at 600 MPa do not show any endothermic peak indicating complete destruction of crystalline structure. Peak and final viscosity of native starches is higher than those of their counterpart high pressure treated starches except waxy corn starch. Increase in gel firmness and destruction of internal structure of starches especially that of tuber starches treated at high pressures is observed. HPT lowered rapidly digestible starch fraction and increased slowly digestible starch and resistant starch fraction. [ABSTRACT FROM AUTHOR]

This work is devoted to an investigation of the magnetic properties and thermal behaviour of the natural oxoborates vonsenite and hulsite in the temperature range 5–500 K. The local environment, the oxidation states of the Fe and Sn atoms, and the charge distribution were determined using Mössbauer spectroscopy and are in accordance with a refinement of the crystal structure of hulsite from single‐crystal X‐ray diffraction data (SCXRD) in anisotropic approximation for the first time. The magnetic properties were studied by vibrating sample magnetometry (VSM) (5 ≤ T ≤ 400 K) and are reported for the first time for iron‐rich hulsite. Both oxoborates show a very complex magnetic behaviour. Cascades of magnetic transitions are revealed and the critical temperatures were determined. The sequences of magnetic transitions in both vonsenite and hulsite with increasing temperature were found to be as follows: magnetically ordered state → partial magnetic ordering → paramagnetic state. According to X‐ray diffraction data (93 ≤ T ≤ 500 K), these processes are accompanied by anomalies in the unit‐cell parameters and thermal expansion of the oxoborates at critical temperatures. A strong negative volume thermal expansion is observed for both oxoborates at temperatures below ∼120 K. [ABSTRACT FROM AUTHOR]

Reactions of Ni(NCS)2 and 3‐cyanopyridine in different solvents lead to the formation of Ni(NCS)2(3‐cyanopyridine)4 (1) already reported in the literature, Ni(NCS)2(3‐cyanopyridine)2(H2O)2 (2), Ni(NCS)2(3‐cyanopyridine)2(CH3OH)2 (3), Ni(NCS)2(3‐cyanopyridine)2(CH3CN)2 (4) and Ni(NCS)2(3‐cyanopyridine)2 (5). The crystal structures of 1–4 consist of discrete octahedral complexes, in which the thiocyanate anions, as well as the 3‐cyanopyridine coligands, are only terminally N‐bonded. In compound 5 the Ni cations are octahedrally coordinated and linked by pairs of thiocyanate anions into dinuclear units that are further connected into layers by single μ‐1,3‐bridging anionic ligands. TG‐DTA measurements of the discrete complex 1 reveal that in the first step half of the coligands are emitted leading to the formation of compound 5. In contrast, compounds 2 and 3 transform into a new crystalline phase of the same composition (6) upon heating that should also contain μ‐1,3‐bridging anionic ligands, but the outcome of this reaction strongly depends on the reaction conditions. The acetonitrile complex 4 is unstable at room temperature and decomposes into a mixture of different phases including the aqua complex 2. Magnetic measurements of compound 5 prove a ferromagnetic transition at Tc=6.0 K. This result is compared to those obtained for other thiocyanate compounds exhibiting a similar layer topology. [ABSTRACT FROM AUTHOR]

The halogenido stannates(II) [BMIm][Sn3Cl7] and [BMIm][Sn4Br9] are obtained by ionic‐liquid‐based synthesis with SnX2 and [BMIm]X (X=Cl, Br; [BMIm]=1‐butyl‐3‐methylimidazolium) near room temperature (45–50 °C). Both form colorless, moisture‐sensitive crystals and exhibit layered anionic networks. [BMIm][Sn3Cl7] contains "horseshoe"‐like ∞1(SnCl1/1Cl2/2) chains that are linked via [SnCl3]− anions to ∞2[Sn3Cl7]− zigzag‐planes. [BMIm][Sn4Br9] contains a complex ∞2[Sn4Br9]− network with altogether four different crystallographic Sn2+ sites and different coordination. For comparison with these complex halogenido stannates(II), PbCl2/PbBr2 are reacted with similar conditions, which, however, only results in [BMIm][PbCl3] containing ∞1[PbCl3]− chains. Beside the crystal structures, the thermal and optical properties are examined and feature certain emission of visible light for all title compounds at room temperature. Whereas the quantum yields of [BMIm][Sn4Br9] (3 %) and [BMIm][PbCl3] (21 %) are low, [BMIm][Sn3Cl7] shows surprisingly efficient photoluminescence with a quantum yield of 46 %. [ABSTRACT FROM AUTHOR]

This study aimed to understand the effect of the acidified hydroethanolic solution (AHS) with different ethanol concentrations (50%, 60%, 70%, 80%, and 96%) on the physicochemical properties of potato and cassava starch nanoparticles (NPs) obtained by anti‐solvent precipitation (AP). The recovery efficiency (RE) is investigated, and the starch NPs are characterized by particle size, surface charge, chemical bonds, crystalline structure, thermal properties, moisture content, water activity, solubility in water, and swelling factor. The best potato and cassava starch NPs are added in gelatin gummies and they are studied by texture profile analysis. The starch NPs have particle size lower than 1000 nm and V‐type crystalline structure. Furthermore, these nanomaterials showed high solubility values in water at 30 and 90 °C. In general, the ethanol concentration used in the AHS altered the RE, particle size, and surface charge of nanoparticles. Texture properties of gelatin gummies containing starch NPs are similar when compared with those gummies manufactured with native starches. The starch NPs could be used to substitute native starches in gelatin gummies. This research reports for the first‐time information regarding the food application of starch NPs, being that these nanomaterials could be used in food productssensitive to heating. [ABSTRACT FROM AUTHOR]

Phenibut is an anxiolytic drug approved for medical use in many eastern European states. With the exception of the HCl Salt of Phenibut no crystal structure related research has been conducted on this substance. Herein, the crystal structures of Phenibut and Phenibut·H2O are presented, including crystal packing analysis based on interaction energy calculations. IR spectra are shown alongside powder diffraction data and thermogravimetric analysis to characterize and compare structural as well as thermal properties of the examined Phenibut forms. Single crystal diffraction is used in conjunction with Crystal Explorer based Hirshfeld analysis to carefully identify the bonding interaction properties in each compound. Finally, a case is made regarding stability of the compared crystalline phases based on the conducted structural analyses and the quantification of the molecular interaction energies. [ABSTRACT FROM AUTHOR]

Two new metal coordination complexes, namely, poly[aqua(μ6‐benzene‐1,2,4,5‐tetracarboxylic acid‐κ8O1:O1,O2:O2′:O4:O4,O5:O5′)(μ‐but‐2‐enedioato‐κ2O1:O4)potassium(I)], [K2(C4H2O4)(C10H6O8)(H2O)2]n or [K2(fum)(H4btec)(H2O)2]n, (1), and poly[aqua(μ8‐2,5‐dicarboxybenzene‐1,4‐dicarboxylato‐κ12O1:O1′,O2:O2,O2′:O2′:O4:O4′,O5:O5,O5′:O5′)(μ‐ethanedioato‐κ4O1,O2:O1′,O2′)strontium(II)], [Sr2(C2O4)(C10H4O8)(H2O)2]n or [Sr2(ox)(H2btec)(H2O)2]n, (2) (H4btec = benzene‐1,2,4,5‐tetracarboxylic acid, H2btec = 2,5‐dicarboxybenzene‐1,4‐dicarboxylate, fum = fumarate and ox = oxalate), have been obtained under hydrothermal conditions by reacting the different alkali and alkaline earth metal salts with H4btec, fumaric acid (H2fum) and oxalic acid (H2ox). Complexes (1) and (2) were structurally characterized by single‐crystal X‐ray diffraction, IR and UV–Vis spectroscopy, powder X‐ray diffraction (PXRD) and thermogravimetic analysis–differential scanning calorimetry (TGA–DSC). Complex (1) displays a two‐dimensional (2D) layer with the K+ ion in a distorted pentagonal bipyramidal geometry and exhibits a uninodal 6‐connected hxl/Shubnikov plane net (3,6) with {36.46.53} topology. Complex (2) displays a three‐dimensional (3D) network structure, in which the Sr2+ ion is in a distorted monocapped square antiprism geometry. The framework possess a binodal (5,8)‐connected net with the Schläfli symbol {32.410.58.64.74}{32.46.52}2. The 3D Hirshfeld surfaces and 2D fingerprint plots show that the main interactions are the O...H/H...O intermolecular interactions. Moreover, the thermal decompositions of (1) and (2) in the temperature range 303–1273 K revealed that they both decompose in three steps and transform to the corresponding metal oxide. [ABSTRACT FROM AUTHOR]

Bis(5‐amino‐1,2,4‐triazol‐4‐ium‐3‐yl)methane dinitrate, BATZM·(NO3)2 or C5H10N82+·2NO3−, was synthesized and its crystal structure determined by single‐crystal X‐ray diffraction. It crystallizes in the space group Pbcn (orthorhombic) with Z = 4. BATZM·(NO3)2 is a V‐shaped molecule where hydrogen bonds form a two‐dimensional corrugated sheet with reasonable chemical geometry and no disorder. The specific molar heat capacity (Cp,m) of BATZM·(NO3)2 was determined using the continuous Cp mode of a microcalorimeter and theoretical calculations, and the Cp,m value is 366.14 J K−1 mol−1 at 298.15 K. The relative deviations between the theoretical and experimental values of Cp,m, HT – H298.15K and ST – S298.15K of BATZM·(NO3)2 are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) were estimated using the nitrogen equivalent equation according to the experimental density; BATZM·(NO3)2 has a higher detonation velocity (7927.47 ± 3.63 m s−1) and detonation pressure (27.50 ± 0.03 GPa) than 2,4,6‐trinitrotoluene (TNT). The above results for BATZM·(NO3)2 are compared with those of bis(5‐amino‐1,2,4‐triazol‐3‐yl)methane (BATZM) and bis(5‐amino‐1,2,4‐triazol‐4‐ium‐3‐yl)methane dihydrochloride (BATZM·Cl2), and the effect of nitrate formation is discussed. [ABSTRACT FROM AUTHOR]

Bis(5‐amino‐1,2,4‐triazol‐4‐ium‐3‐yl)methane dichloride (BATZM·Cl2 or C5H10N82+·2Cl−) was synthesized and crystallized, and the crystal structure was characterized by single‐crystal X‐ray diffraction; it belongs to the space group C2/c (monoclinic) with Z = 4. The structure of BATZM·Cl2 can be described as a V‐shaped molecule with reasonable chemical geometry and no disorder, and its one‐dimensional structure can be described as a rhombic helix. The specific molar heat capacity (Cp,m) of BATZM·Cl2 was determined using the continuous Cp mode of a microcalorimeter and theoretical calculations, and the Cp,m value is 276.18 J K−1 mol−1 at 298.15 K. The relative deviations between the theoretical and experimental values of Cp,m, HT – H298.15K and ST – S298.15K of BATZM·Cl2 are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) of BATZM·Cl2 were estimated using the nitrogen equivalent equation according to the experimental density; BATZM·Cl2 has a higher detonation velocity (7143.60 ± 3.66 m s−1) and detonation pressure (21.49 ± 0.03 GPa) than TNT. The above results for BATZM·Cl2 are compared with those of bis(5‐amino‐1,2,4‐triazol‐3‐yl)methane (BATZM) and the effect of salt formation on them is discussed. [ABSTRACT FROM AUTHOR]

Reaction of MX2 (M = Cd, Zn; X = Cl, Br, I) with 2‐cyanopyrazine leads to the formation of compounds with the composition CdX2(2‐cyanopyrazine)2 (X = Cl; CdCl, X = Br; CdBr and X = I; CdI) and ZnX2(2‐cyanopyrazine)2 (X = Cl; ZnCl, X = Br; ZnBr and X = I; ZnI/I). In the crystal structures of the Cd compounds and in ZnCl, the metal cations are octahedrally coordinated and are linked into chains by the halide anions via common edges. In contrast, in the crystal structures of ZnBr and ZnI/I the metal cations are tetrahedrally coordinated into discrete complexes. Further investigations show that a second modification of ZnCl2(2‐cyanopyrazine)2 exists (ZnI/II), which is formed by kinetic control. The thermal properties of the 2‐cyanopyrazine rich compounds were investigated by TG‐DTA and temperature dependent XRPD measurements. Upon heating the Cd compounds, all 2‐cyanopyrazine ligands are removed in a single step with no indication of the formation of a 2‐cyanopyrazine deficient phase. A similar behavior is observed for ZnI, whereas for ZnCl and ZnBr, TG‐DTA measurements suggest the formation of a 2‐cyanopyrazine deficient phase that, in case of ZnBr, cannot be isolated and, for ZnCl, cannot be obtained pure. The emission of these compounds is shifted from the blue to orange depending on the crystal structure and the nature of the halide anion. [ABSTRACT FROM AUTHOR]

Phase‐pure polycrystalline samples of GdTe1.8 and GdTe1.76As0.04 were synthesized by reacting Gd2Te3 with elemental Te and As, employing a small amount of I2 as mineralizer. Polycrystalline specimens were densified by SPS for temperature dependent electrical and thermal properties investigations. The electrical properties indicate that arsenic doping leads to a change from n‐ to p‐type conduction, with an order‐of‐magnitude reduction in resistivity with As doping at room‐temperature as compared to GdTe1.8. The thermal conductivity of both specimens is low, the result of the crystal structure and atypical Te bonding in this material. The results presented are intended to expand on the research into rare‐earth polychalcogenides and advance the fundamental investigation of these materials, as well as begin to evaluate their potential for thermoelectric applications. [ABSTRACT FROM AUTHOR]

Trans‐A2B2 porphyrins containing p‐methoxyphenyl (A)/p‐methylphenyl (B) (P4) and p‐chlorophenyl (A)/p‐methylphenyl (B) (P5) at the four meso (−CH=) positions of the tetrapyrrolic macrocycles have been synthesized by employing the two steps modified Adler's methodology. Remarkably, the present synthetic scheme afforded us the needle shaped single crystals of (P4) and (P5) that helped us investigate the three dimensional structural architectures of the prepared Trans‐A2B2 porphyrins. Hirschfeld surface analysis (HSs) was used to visualize the fidelity of the crystal structures of (P4) and (P5). This method permitted the identification of individual types of intermolecular contacts and their impact on crystal packings. Molecules are linked by a combination of H⋅ ⋅ ⋅H and C⋅ ⋅ ⋅H contacts, which have clear signatures in the corresponding fingerprint plots. The effect of incorporating two different non sterically demanding functionalities at the para positions of meso phenyl rings on the optical and thermal properties of symmetric (A4) porphyrins i. e. Tetra‐para‐methoxy phenyl porphyrin P1, Tetra‐para‐methyl phenyl porphyrin P2 and Tetra‐para‐chloro phenyl porphyrin P3, have been investigated and the results have been discussed in detail. [ABSTRACT FROM AUTHOR]

A series of new mono‐ and bis‐terpyridine complexes [Mn(tpyOH)Cl2] (1), [Ni(tpyOH)2](PF6)2 (2) and [Zn(tpyO)(η1‐OCOCH3)(H2O)]⋅3H2O (4) containing 4′‐hydroxy‐2,2′:6′,2″‐terpyridine (tpyOH) were synthesized and structurally characterized using elemental analysis, infrared spectroscopy and single‐crystal X‐ray diffraction. The reaction of MnCl2 with tpyOH in a mixture of methanol and CH2Cl2 resulted in the formation of 1. The X‐ray crystal structure of 1 reveals that Mn(II) is penta‐coordinated by three nitrogen atoms from tpyOH and two Cl− in a slightly distorted trigonal bipyramidal geometry. Complex 2 was also prepared by the reaction of nickel(II) chloride with tpyOH in a methanolic medium in the presence of NH4PF6. Notably, the complex [Ni(tpyOH)(tpyO)]PF6 (3), obtained during the crystallization of 2 from dichloromethane, was characterized using X‐ray crystallography which shows that six nitrogen atoms from terpyridine ligands occupy the coordination sites around the Ni(II) centre in a distorted octahedral geometry with four longer bonds and two shorter NiN bonds. The reaction of zinc(II) acetate with tpyOH in a mixture of methanol and CH2Cl2 led to the formation of 4. The crystal structure of 4 reveals the formation of penta‐coordinated Zn(II) complex containing three nitrogen atoms from tpyO, a monodentate acetate ligand and one coordinated water molecule. Hirshfeld surface analyses and two‐dimensional fingerprint plots show that the main interactions are O...H/H...O contacts in 1, 3 and 4. The thermal decomposition reactions of 1, 2 and 4 were studied using thermogravimetric analysis in detail due to their different structures. The solution luminescence features of 1, 2 and 4 include high‐energy intense π → π* intraligand and low‐energy metal‐to‐ligand charge transfer transitions at room temperature. The calcination of the coordination complexes led to the formation of corresponding nano metal oxides. The products were structurally characterized using infrared spectroscopy, scanning electron microscopy and energy‐dispersive X‐ray spectroscopy. The average particle size using Scherrer's equation was calculated to be below 50 nm. [ABSTRACT FROM AUTHOR]

The judicious selection of suitable ligands is vitally important in the construction of novel metal–organic frameworks (MOFs) with fascinating structures and interesting properties. Recently, imidazole‐containing multidentate ligands have received much attention. Two new CdII coordination frameworks, namely, poly[tris{μ‐1,4‐bis[(1H‐imidazol‐1‐yl)methyl]benzene‐κ2N3:N3′}tetrakis(nitrato‐κ2O,O′)dicadmium], [Cd2(NO3)4(C14H14N4)3]n, (I), and poly[[bis{μ3‐1,3,5‐tris[(1H‐imidazol‐1‐yl)methyl]benzene‐κ3N3:N3′:N3′′}cadmium] hexafluorosilicate], {[Cd(C18H18N6)2](SiF6)}n, (II), have been synthesized and characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. In polymer (I), the 1,4‐bis[(1H‐imidazol‐1‐yl)methyl]benzene ligand bridges Cd2+ ions with a distorted seven‐coordinated pentagonal bipyramidal geometry, forming a one‐dimensional ladder chain, and the nitrate anions coordinate to the Cd2+ ions in a terminal bidentate fashion. In the crystal, adjacent chains are further connected by C—H...O hydrogen bonds to generate a two‐dimensional (2D) supramolecular structure. Polymer (II) exhibits a 2D layered structure in which 1,3,5‐tris[(1H‐imidazol‐1‐yl)methyl] benzene ligands join Cd2+ centres having a six‐coordinated octahedral structure. The layers are connected by hexafluorosilicate anions via C—H...F hydrogen‐bond interactions, giving rise to a three‐dimensional supramolecular network structure in the solid state. In addition, powder X‐ray diffraction (PXRD) patterns were recorded, thermogravimetric analyses (TGA) carried out and fluorescence properties investigated. [ABSTRACT FROM AUTHOR]

The room temperature reaction of Na4Sn2S6·5H2O with CoCl2·6H2O and 2‐(aminomethyl)pyridine (2‐AMP) or trans‐1,2‐diamino‐cyclohexane (DACH) leads to crystallization of two compounds with the compositions [Co(2‐(aminomethyl)pyridine)3]2 Sn2S6·10H2O (1) and [Co(trans‐1,2‐diaminocyclohexane)3]2Sn2S6·8H2O (2). In both compounds [Sn2S6]4– anions are present that are charge balanced each by two Co2+ centered complexes. Each of the two CoII cations are sixfold coordinated by six N atoms of three 2‐AMP or DACH ligands within slightly distorted octahedra. In compound 1, the two complexes are linked by one [Sn2S6]4– anion via strong N–H···S hydrogen bonds into centrosymmetric charge neutral trimeric units, that are further linked by weak C–H···S and N–H···S hydrogen bonds into chains that are directed along the a axis. These chains are further joined by N–H···O and O–H···O hydrogen bonds into a 3D network, with the H2O molecules forming chains along the b axis. The crystal structure of 2 is similar to that of 1 featuring trimeric units which are also linked into chains. Between the chains water molecules are embedded that link the chains into a 3D network. Upon heating 2 in a thermobalance the water and ligand molecules are removed in discrete steps, indicating that compounds with more condensed thiostannate networks will form. [ABSTRACT FROM AUTHOR]

The new compound {[Fe(cyclam)]3Nb7O22}· ≈ 19 H2O (I) was synthesized at room temperature reacting aqueous solutions of K8{Nb6O19}·16 H2O, Fe(NO3)3·9 H2O and cyclam (1,4,8,11‐tetraazacyclotetradecane). In the crystal structure the heptaniobate {Nb7O22}9– anion is observed which is expanded by three [Fe(cyclam)]3+ complexes, thus suppressing further condensations into larger aggregates. The complexes are solely bound to the three terminal O2– anions of the NbO6 octahedron which expands the hexaniobate {Nb6O19}8– anion to form the heptaniobate cluster. The two O atoms in the FeN4O2 octahedron are in cis position leading to a severe distortion of the cyclam ligand with one of the CH2–CH2–CH2–N–CH2–CH2 fragments being rotated by about 90°. The {[Fe(cyclam)]3Nb7O22} units are arranged to form channels which host the crystal water molecules. The crystal water molecules can be removed by thermal treatment. Storing the sample on air the pristine sample is recovered. [ABSTRACT FROM AUTHOR]

New adducts with the composition [Co2Gd(NO3)(Piv)6L2] (L=2,4‐lutidine (lut) (1), 2‐phenylpyridine (PhPy) (4), 2‐ethynylpyridine (EtPy) (5)) and [Co2Eu(NO3)(Piv)6(EtPy)2] (6) were synthesized. According to X‐ray diffraction data, the molecular complexes comprise two atoms of cobalt(II) and one central atom of gadolinium(III) bridged by carboxylate ligands. The donor base molecules are coordinated to cobalt atoms. Magnetic measurements of the new and previously synthesized complexes with quinoline (2) and pyridine (3) ligands showed the ferromagnetic nature of the coupling between the metal centers in the CoII2GdIII core with JCo‐Gd parameters in the range of 0.15−0.18 cm−1. DFT calculations supported the ferromagnetic type of coupling for these complexes. Simultaneous thermal analysis of 1 and 2 showed the thermal stability of the complexes up to 180 °C and the stepwise nature of thermolysis, which includes the stages of elimination of the donor base molecules and the thermal decomposition of the pivalate moieties in the complex. [ABSTRACT FROM AUTHOR]

The reaction of 3‐Amino coumarin based Schiff base ligands HL1 and HL2 with metal acetates in refluxing ethanol affords access to a new series of neutral mononuclear divalent complexes [MII‐κ3‐bis‐O,N,O‐tridentate Schiff base‐ HL1/ HL2] {HL1, MII=Co (1), Ni (2) or Zn (3); HL2, MII=Co (4), Ni (5) or Zn (6)}, [CuII‐κ2‐bis‐N,O‐bidentate Schiff base‐HL1] (7) and [CuII‐κ2‐bis‐N,O‐bidentate Schiff base‐HL2] (8). Compounds were characterized by microanalysis, standard spectroscopic (viz. MALDI‐TOF‐MS, IR, 1H and 13C NMR, UV‐visible absorption and emission) and TGA/DTA methods. The unambiguous crystal structure of HL1, HL2, complexes 2 and 3 was determined crystallographically. The IR, UV‐visible, EPR spectral and magnetic studies clearly suggest the κ3‐O,N,O‐tridentate‐ coordination mode of HL1 and HL2 towards cobalt(II), nickel(II) and zinc(II) metal ions in 1–6 and κ2‐N,O‐bidentate‐coordination mode towards copper(II) metal ions in 7 and 8. Notably, compounds fluoresce a medium to strong emissions in the visible region is observed with concomitant Stokes shifts of ≈ 90 nm. UV‐visible transmittance spectral study reveals the semiconducting nature of HL1, HL2, complexes 1–8 gave with band gap energy of 1.57‐2.24 electron volts. The molecules of HL1, HL2, 2 and 3 are stabilized by various intermolecular CH...π, CH...O and π...π contacts that efficiently managed the growth of self‐assembly in three dimensions and form infinite molecular layers in the solid state. [ABSTRACT FROM AUTHOR]

Crystallographic, thermal and stability analyses are presented of three different anhydrated forms of bendamustine hydrochloride [(I), (III) and (IV)] and a fourth, monohydrated one (II). Since form (I) presents the higher melting point and the higher heat of fusion, according to the 'heat of fusion' rule it should be the most stable in thermodynamic terms [Burger & Ramberger (1979). Mikrochim. Acta, 72, 259–271], though it is unstable in high‐humidity conditions. The monohydrate structure (II), in turn, dehydrates by heating and topotactically transform into anhydrate (III). This latter form appears as less stable than anhydrate (I), to which it is linked via a monotropic relationship. For these three different forms, the crystal structure has been determined by single crystal X‐ray diffraction. The crystal structures and molecular conformations of forms (II) and (III) are quite similar, as expected from the topotactic transformation linking them; furthermore, under high‐humidity conditions, form (III) shows changes compatible with a transformation into form (II) within 24 h. The crystal structure of form (I) is different from the other two. The remaining polymorphic form (IV) could only be obtained as a powder, from which its crystalline structure could not be determined. The relative thermodynamic stability of the different crystalline forms was determined by differential scanning calorimetry and thermogravimetrical studies, and their stability under different humidity conditions analysed. [ABSTRACT FROM AUTHOR]

The new compound {[Cu(cyclam)]2[Sn2S6]}n·2nH2O containing Cu(II) was synthesized at room temperature reacting aqueous solutions of Na4SnS4·14H2O and of [Cu(cyclam)](ClO4)2. A crystalline precipitate consisting of small crystallites was formed after a very short reaction time of 2 h. Structure analysis reveals that [Sn2S6]4– anions are joined by the [Cu(cyclam)]2+ cations via Cu–S bonds generating layers which are stacked along the crystallographic a‐axis. The Cu(II) centers are in a distorted octahedral environment of four N and two S atoms. The distortion is reflected in the EPR spectrum that displays the A∥ lines characteristic for Cu2+ (I = 3/2) and due to g∥ > g⊥ > 2.0023, the unpaired electron is located in the dx2–y2 orbital. The crystal water molecules can be removed at elevated temperatures, while crystallinity of the sample is mainly retained. Storage of the dehydrated sample on air leads to water uptake and recovery of the pristine compound. [ABSTRACT FROM AUTHOR]

Reaction of Na2S with SnCl4·5H2O in aqueous alkaline sodium hydroxide solution leads to the formation of Na5[SnS4]Cl·13H2O (1). The compound crystallizes monoclinic in space group P21/m with two formula units in the unit cell. In the crystal structure the Na+ cations are octahedrally coordinated and are linked into layers by bridging water molecules, μ3 bridging Cl– anions and μ1,1 bridging S atoms of [SnS4]4– anions. Extended hydrogen bonding interactions generate a three‐dimensional network. Investigations using differential thermoanalysis, thermogravimetry, and differential scanning calorimetry shows that upon heating in open crucibles the water can be removed leading to the formation of the anhydrate that is stable at room temperature and does not transform back into compound 1. Storage of the anhydrate in a desiccator over a water atmosphere leads first to formation of Na4SnS4·14H2O followed by crystallization of the title compound. After longer storage times NaCl appears as a second crystalline phase. If the thermal measurements are performed in a self‐produced atmosphere, compound 1 transforms partly into Na4SnS4·14H2O with an increasing amount of this phase with increasing temperature. Synthetic investigations reveal that crystallization of compound 1 sensitively depends on the water content of acetone, which is used for precipitation of 1. Reacting Na4SnS4·14H2O directly with NaCl afforded formation of complex mixtures. [ABSTRACT FROM AUTHOR]

A potassium borate, K5B19O31, has been obtained via the high‐temperature solid‐state reaction. The single crystal for K5B19O31 with dimensions up to 4 mm × 2 mm × 1 mm was grown by the top‐seeded solution growth method. The crystal structure of K5B19O31 shows a complex three‐dimensional (3D) frame filled by three different types of K‐based polyhedra. Optical properties and thermal behavior of K5B19O31 were carried out. The transmission spectrum of K5B19O31 shows that it possesses a UV optical cut‐off edge lower than 180 nm. The birefringence was calculated to be about 0.05 at 1064 nm. Structure‐property relationships were further illuminated via the first‐principles calculation methods. [ABSTRACT FROM AUTHOR]

Antioxidants can effectively protect vegetable‐oil‐based lubricants against oxidative degradation and prolong their service life. A novel compound, (E)‐4‐({3,5‐di‐tert‐butyl‐2‐[(diphenylboranyl)oxy]benzylidene}amino)‐N‐phenylaniline (BSPD) or {2‐[(4‐anilinophenyl)iminomethyl‐κN]‐4,6‐di‐tert‐butylphenolato‐κO}diphenylboron, C39H41BN2O, was synthesized by a one‐pot reaction of the Schiff base bridged phenolic diphenylamine 2,4‐di‐tert‐butyl‐6‐{N‐[4‐(phenylamino)phenyl]carboximidoyl}phenol (SPD) with phenylboronic acid. The corresponding single‐crystal X‐ray study revealed that the B atom in BSPD has a typical tetrahedral geometry, and the N,O‐chelated six‐membered ring adopts a chair conformation. According to thermogravimetric analysis, the 5% weight‐loss temperature of BSPD increases to 328 °C and the 95% weight‐loss temperature is up to 414 °C. More importantly, the antioxidant capability of BSPD in vegetable oil is much better than that of commercial antioxidants [diphenylamine (DPA) and 2,6‐di‐tert‐butyl‐4‐methylphenol (BHT)] and unmodified SPD. [ABSTRACT FROM AUTHOR]

Nitro compounds have been actively researched as driven by their potential to be high‐performing energetic materials. Herein, three new nitro compounds including semicarbazide 3,5‐dinitrobenzoate, (SCZ)(DNBA), manganese 3,5‐dinitrobenzoate dihydrate, [Mn(DNBA)2(H2O)2]n, and bis(semicarbazide) manganese(II) 3,5‐dinitrobenzoate, Mn(SCZ)2(DNBA)2, were synthesized and characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction analysis. The results indicated that the above mentioned compounds are ionic, polymeric, and molecular in nature, respectively. Moreover, their thermal decomposition properties were assessed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Their non‐isothermal reaction kinetics parameters, critical temperature of thermal explosion (Tbp), entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) of the exothermic decomposition process were also calculated. Results suggest that there was a relationship between the structure and thermal stability. [ABSTRACT FROM AUTHOR]

Non‐functionalized and n‐alkyl‐functionalized siloxane‐silsesquioxane resins (S4SQ) were synthesized and characterized to confirm their structure and properties. Polypropylene (PP) composites with S4SQ resins as fillers were prepared by the melt blending. The influence of the kinds and amounts of fillers on the structural, morphological and thermal properties as well as mechanical characteristics and processability was determined. High compatibility of composites with functionalized resins resulted in more homogenous dispersion of filler particles in comparison with the composites which contained a non‐functionalized resin. Moreover, the introduction of S4SQ resins into PP strongly affected the crystalline structure of the polymer matrix and the free‐volume properties of composites. Siloxane‐silsesquioxane resins changed the contributions of the α‐ and β‐crystalline phases and they increased the crystal sizes of PP. The PP/S4SQ composites were also characterized by the improved crystallization temperature and crystallinity degree while the melting temperature and processability were changed only slightly. The mechanical properties of the PP/S4SQ materials were found to be dependent mostly on the degree of filler dispersion and crystalline structure of the composite materials. POLYM. COMPOS., 40:3101–3114, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Although coordination polymers generally do not melt, several that do melt have been synthesized recently and have drawn much attention. In this study, two‐ and three‐dimensional coordination polymers that melt were synthesized, [Ru(Cp)(C6H5R)][M{C(CN)3}2] (R=H, Me, Et; M=K, Rb; Cp=C5H5), which are complex salts comprising M[C(CN)3] and organometallic ionic liquids [Ru(Cp)(C6H5R)][C(CN)3]. They have anionic [M{C(CN)3}2]n− coordination polymer frameworks, whose dimensionalities depend on the size of the organometallic cation inside. Their melting points decreased with increasing cation substituent length and size of the alkali metal ion (Tm=102–239 °C), and these low‐melting‐point coordination polymers exhibited incongruent melting, forming mixtures of solid M[C(CN)3] and ionic liquid upon melting. Using the same method, coordination polymers were synthesized with various bridging ligands, [Co(Cp)2][MX2] (X=B(CN)4, C(CN)3, N(CN)2; M=K, Na), as well as a paramagnetic coordination polymer, [Fe(Cp)2][K{C(CN)3}2]. [ABSTRACT FROM AUTHOR]

The new transition metal oxo‐thiostannate {[Ni(cyclen)]6[Sn6S12O2(OH)6]}·2(ClO4)·19H2O (1) was prepared under hydrothermal conditions using Na4SnS4·14H2O and [Ni(cyclen)](ClO4)2 as reactants. In the crystal structure the rare [Sn6S12O2(OH)6]10– anion is observed, which is composed of SnS2O(OH)3 and SnS4O2 octahedra, and SnS4 tetrahedra sharing edges and corners. The anion is expanded by six Ni2+ centered complexes via Ni–S and Ni–OH bonds. The photocatalytic properties for the visible light driven hydrogen evolution reaction shows that 26.6 mmol·g–1 H2 were evolved after 3 h. [ABSTRACT FROM AUTHOR]

The reaction of different stoichiometric amounts of Zn(NCS)2 with 3‐cyanopyridine in different solvents leads to the formation of several new coordination compounds, which were structurally characterized and investigated for their thermal behavior. In Zn(NCS)2(3‐cyanopyridine)4 (1) and Zn(NCS)2(3‐cyanopyridine)2(H2O)2·(3‐cyanopyridine)2 (2) the zinc cations are octahedrally coordinated by two terminally N‐bonded thiocyanate anions and four 3‐cyanopyridine (1) or two 3‐cyanopyridine and two water molecules (2) within slightly distorted octahedra. Zn(NCS)2(3‐cyanopyridine)2 (3) and Zn(NCS)2(3‐cyanopyridine)2·(H2O)0.5 (3‐H2O) also form discrete complexes but with tetrahedrally coordinated Zn cations. Upon heating compound 1 decomposes without the formation of any intermediate compound. In contrast, compound 2 loses the water molecules in the first step and transforms into compound 1. Surprisingly, upon further heating a second TG step is observed, in which compound 3 is formed as an intermediate, which is not observed if compound 1 is heated directly. The tetrahedral complex 3 melts leading to the formation of an amorphous phase. If the hemihydrate 3‐H2O is heated, it transforms into 3 via melting and crystallization but there are hints that a metastable phase might form as intermediate on water removal. [ABSTRACT FROM AUTHOR]

Salts of cationic sandwich complexes often exhibit an ionic plastic phase; however, only a few exhibit a plastic phase at room temperature. To explore the use of the CF3BF3 anion to lower the transition temperature to the plastic phase, we prepared salts of CF3BF3 with various ferrocene derivatives, [D][CF3BF3] (D=FeCp*2, Fe(C5Me4H)2, Fe(C5H4Me)2, FeCp(C5H4Me), FeCp2; Cp*=C5Me5, Cp=C5H5). Although [FeCp*2][CF3BF3] exhibited a plastic phase above 417 K, the other salts formed room‐temperature ionic plastic crystals with a phase transition to the plastic phase in the range 266–291 K. The crystal structure and thermal properties of [FeCp2][OTf] were elucidated for comparison. In addition, decamethylferrocenium salts with other anions were synthesized and structurally characterized: [FeCp*2][X] (X=N(SO2F)2 and B(CN)4) exhibited a phase transition to the plastic phase above 400 K, whereas carborane‐containing salts [FeCp*2]2[B12F12] and [FeCp*2][Co(C2B9H11)2] did not exhibit a plastic phase. Phase transitions, crystal structures, and magnetic properties of salts of ferrocene derivatives with CF3BF3− and other anions were investigated. Most of the CF3BF3 salts exhibited a plastic phase at room temperature. [ABSTRACT FROM AUTHOR]

The acidity of the amine H atoms and the consequent salt formation ability of ethylenedinitramine (EDNA) were analyzed in an attempt to improve the thermal stability of EDNA. Two short‐chain alkanediamine bases, namely propane‐1,3‐diamine and butane‐1,4‐diamine, were chosen for this purpose. The resulting salts, namely propane‐1,3‐diaminium N,N′‐dinitroethylenediazanide, C3H12N22+·C2H4N4O42−, and butane‐1,4‐diaminium N,N′‐dinitroethylenediazanide, C4H14N22+·C2H4N4O42−, crystallize in the orthorhombic space group Pbca and the monoclinic space group P21/n, respectively. The resulting salts display extensive hydrogen‐bonding networks because of the presence of ammonium and diazenide ions in the crystal lattice. This results in an enhanced thermal stability and raises the thermal decomposition temperatures to 202 and 221 °C compared to 180 °C for EDNA. The extensive hydrogen bonding present also plays a crucial role in lowering the sensitivity to impact of these energetic salts. Two novel energetic salts of ethylenedinitramine (EDNA) with alkanediamines have been crystallized and analyzed for their thermal properties. The extensive hydrogen‐bonding networks in the energetic salts serve to improve their friction and shock sensitivity. [ABSTRACT FROM AUTHOR]

Two polymorphs of Ni(NCS)2(4‐methoxypyridine)4 (1‐I, 1‐II) as well as compounds with the compositions Ni(NCS)2(4‐methoxypyridine)4(MeCN)1.33 (1‐MeCN), Ni(NCS)2(4‐methoxypyridine)2(MeCN)2 (2) and [Ni(NCS)2(4‐methoxypyridine)2]n (3) are reported. For 1‐II no single crystals were obtained, but this compound is isotypic to the Fe analog 1‐II‐Fe. The crystal structures of 1 and 2 show discrete octahedral NiII complexes, whereas in 3 the cations are connected by pairs of thiocyanate anions into chains. Solvent mediated conversion experiments reveal that 1‐I is thermodynamically stable at room temperature and differential scanning calorimetry shows no indication for a polymorphic transition. The thermal behavior of 1‐I, 1‐II, and 2 was investigated by simultaneous thermogravimetry and differential scanning calorimetry, which shows that they decompose in two discrete steps. In the first step compound 3 is formed as an intermediate, which decomposes on further heating into Ni(NCS)2. Time dependent XRPD investigations prove, that 2 transforms already at room temperature into 3. Upon heating 1‐MeCN transforms into 1‐I in the first TG step, which decomposes on further heating into 3. Investigation of the magnetic behavior of 3 shows dominating ferromagnetic exchange interactions along the chains with J = 5.9(1) K. Susceptibility measurements indicate antiferromagnetic ordering, which was confirmed by specific heat measurements, revealing that magnetic ordering occurs at 1.91(5) K. [ABSTRACT FROM AUTHOR]

Reaction of Co(NCS)2 with 4‐dimethylaminopyridine (DMAP) leads to the formation of four new compounds. The crystal structures of Co(NCS)2(DMAP)2(H2O)2·2H2O (1), Co(NCS)2(DMAP)2(MeOH)2 (2) and Co(NCS)2(DMAP)2(MeCN)2 (3) consist of discrete simple solvato complexes in which the Co cations are octahedrally coordinated by two terminally N‐bonded thiocyanate anions, two DMAP ligands as well as two solvato ligands. Co(NCS)2(DMAP)2 (4/II) also forms discrete complexes, but the Co cations are tetrahedral coordinated by two anionic ligands and two DMAP ligands. Upon heating, the hydrate 1 transforms into 4/II, whereas the methanol solvate 2 transforms into a new polymorphic modification of Co(NCS)2(DMAP)2 (4/I). For structure determination the corresponding Zn(NCS)2 compound was prepared that is isotypic to 4/I. Solvent mediated conversion experiments prove that 4/II represents the thermodynamic stable form at room‐temperature and density functional theory (DFT) calculations indicate that this form is also stable at 0 K. Upon heating both modifications show melting with the higher melting polymorph 4/I having the lower melting enthalpy. Temperature dependent X‐ray powder diffraction shows that 4/II transforms into 4/I upon heating. All experimental results indicate, that both modifications are related by enantiotropism. Two polymorphic Co(NCS)2 coordination compounds were synthesized by solvent removal from different precursors, structurally characterized and investigated for their stability, thermodynamic relations and transition behaviour. Both forms are related by enantiotropism and the thermodynamic transition temperature was estimated from their melting enthalpies and confirmed by annealing experiments. [ABSTRACT FROM AUTHOR]

A new unsymmetrical s‐tetrazine derivative, namely 4‐({2‐[6‐(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)‐1,2,4,5‐tetrazin‐3‐yl]hydrazin‐1‐ylidene}methyl)phenol (DPHM), C14H14N8O, was synthesized based on 3‐(3,5‐dimethylpyrazol‐1‐yl)‐6‐hydrazinyl‐s‐tetrazine (DPHT). The structure was characterized by elemental analysis and single‐crystal X‐ray diffraction. Crystal structure determination shows that DPHM crystallizes in the monoclinic P21/c space group with high coplanarity and a zigzag layered structure. In addition, its thermal behaviour was investigated by DSC and TG–DTG methods. The thermal safety of DPHM was evaluated by self‐accelerating decomposition temperature (TSADT), critical temperature of thermal explosion (Tb), entropy of activation (ΔS ), enthalpy of activation (ΔH ) and free energy of activation (ΔG ). Meanwhile, the kinetic parameters and specific heat capacity of DPHM were also determined. The results show that DPHM has better stability and detonation properties than 3‐(2‐benzylidenehydrazin‐1‐yl)‐6‐(3,5‐dimethylpyrazol‐1‐yl)‐s‐tetrazine (DAHBTz), due to the introduction of a hydroxy group, which increases the number of hydrogen‐bond interactions and improves the stability and density of DPHM. This study demonstrates that the performance of an explosive can be optimized through structural modification. [ABSTRACT FROM AUTHOR]

Abstract: Crystalline solids with intrinsically low lattice thermal conductivity (κL) are crucial to realizing high‐performance thermoelectric (TE) materials. Herein, we show an ultralow κL of 0.35 Wm−1 K−1 in AgCuTe, which has a remarkable TE figure‐of‐merit, zT of 1.6 at 670 K when alloyed with 10 mol % Se. First‐principles DFT calculation reveals several soft phonon modes in its room‐temperature hexagonal phase, which are also evident from low‐temperature heat‐capacity measurement. These phonon modes, dominated by Ag vibrations, soften further with temperature giving a dynamic cation disorder and driving the superionic transition. Intrinsic factors cause an ultralow κL in the room‐temperature hexagonal phase, while the dynamic disorder of Ag/Cu cations leads to reduced phonon frequencies and mean free paths in the high‐temperature rocksalt phase. Despite the cation disorder at elevated temperatures, the crystalline conduits of the rigid anion sublattice give a high power factor. [ABSTRACT FROM AUTHOR]

Starch granules derived from certain tuber or root crops exhibit a B-type polymorphic pattern and amylopectin with a high content of long B-chains and comparatively long segments between the building blocks. Here, four B-crystalline starches are selected to study their morphology and molecular composition, including lintnerization conducted at two different temperatures. The structure of the granules suggests that the B-type crystalline starches can be divided into two distinct groups, with potato and edible canna forming one group having large granules with typical "growth rings" and the molecular structure of the lintners being dependent on the temperature of lintnerization. The other group consists of shoti and lesser yam starches possessing granules with alternating "granular slices" instead of rings or shells and the molecular composition of the lintners is not dependent on the temperature. It is found that the former group of starch possess lower gelatinization temperatures and swell at lower temperatures than the latter group, suggesting a more labile granular structure of potato and canna starches compared to shoti and lesser yam. As the properties are not related to the amylose or phosphate content of the granules, the result suggests that B-crystalline starch granules are found as at least two distinct structural types with unique architectures. [ABSTRACT FROM AUTHOR]

Reaction of Cd(NCS)2 or Zn(NCS)2 with 3-aminomethylpyridine (3-AMPY) leads to the formation of five compounds with the compositions [Cd(NCS)2(3-AMPy)2·(3-AMPy)]n (1-Cd), [M(NCS)2(3- AMPy)2]n [M = Cd (2-Cd), Zn (2-Zn)] [Cd(NCS)2(3-AMPy)]n (3-Cd), and [Zn(NCS)2(3-AMPy)]2 (3-Zn). In 1-Cd the Cd cations are linked by the 3-AMPy ligands into layers that consist of rings, built up of four Cd cations and four 3-AMPy ligands. These layers are stacked to form channels, in which the 3-AMPy solvate molecules are located. In the isotypic compounds 2-Cd and 2-Zn the metal cations are also linked into layers by the 3-AMPy ligands with an identical layer topology as that in 1-Cd, but a completely different conformation of the 3-AMPy ligand. In the most 3-AMPy deficient compound 3-Cd, the Cd cations are linked by μ- 1,3-bridging thiocyanate anions and 3-AMPy ligands into chains, that are further connected into layers by additional anionic ligands. In 3-Zn two Zn cations are linked by pairs of 3-AMPy ligands into discrete dimers. Thermoanalysis and X-ray powder diffraction (XRPD) investigations show that upon heating 1-Cd transforms into 2-Cd and 2-Zn into 3-Zn. The compounds 2-Cd, 3-Cd, 2-Zn and 3-Zn present ligand-based luminescence in the blue-green spectral range with maxima between 21276 and 21795 cm-1. [ABSTRACT FROM AUTHOR]

The reaction of Cd(NCS)2 with 3-hydroxymethylpyridine (3-HMPy) leads to the formation of compounds with the composition Cd(NCS)2(3-HMPy)4 ( 1-Cd), Cd(NCS)2(3-HMPy)2 ( 2-Cd) (Cd(NCS)2)2(3-HMPy)3 ( 3-Cd), and (Cd(NCS)2)3(3-HMPy)4 ( 4-Cd). Compound 1-Cd consists of discrete complexes and in 2-Cd the Cd cations are linked into chains by the anionic and the organic co-ligands. In 3-Cd as well as 4-Cd the Cd cations are connected into chains by the thiocyanate anions, which are further linked into layers by the 3-HMPy co-ligands. In contrast, with Zn only one compound with the composition Zn(NCS)2(3-HMPy)2 ·H2O ( 1-Zn-H2O) was characterized by single-crystal X-ray diffraction, which shows a tetrahedral coordination of the Zn cations by two thiocyanate anions and two 3-HMPy ligands. The discrete complexes are arranged to form channels, in which the water molecules are embedded. 1-Zn-H2O cannot be obtained phase pure and detailed investigations reveal, that additional Zn compounds with the composition Zn(NCS)2(3-HMPy)2 · xH2O including an anhydrate ( 1-Zn) can be obtained, which possesses a similar X-ray powder diffraction (XRPD) pattern. 1-Zn was characterized using X-ray powder diffraction analysis. Most compounds were investigated by thermoanalysis, IR and Raman as well as luminescence spectroscopy. [ABSTRACT FROM AUTHOR]

The energetic ionic salt bis(1-aminoguanidin-2-ium) 5,5′-[1,2,4,5-tetrazine-3,6-diylbis(azanediyl)]bis(1 H-1,2,3,4-tetrazol-1-ide) dihydrate, 2CH7N4+·C4H2N142−·2H2O, (I), with a high nitrogen content, has been synthesized and examined by elemental analysis, Fourier transform IR spectrometry, 1H NMR spectroscopy and single-crystal X-ray crystallography. Compound (I) crystallizes in the monoclinic space group P21/ c with two water molecules. However, the water molecules are disordered about an inversion centre and were modelled as half-occupancy molecules in the structure. The crystal structure reveals a three-dimensional network of molecules linked through N-H...N, N-H...O, O-H...N and O-H...O hydrogen bonds. Thermal decomposition was investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The exothermic peak temperature is 509.72 K, which indicates that hydrated salt (I) exhibits good thermal stability. Non-isothermal reaction kinetic parameters were calculated via both the Kissinger and the Ozawa methods to yield activation energies of Ek = 239.07 kJ mol−1, lg Ak = 22.79 s−1 and EO = 235.38 kJ mol−1 for (I). Additionally, the thermal safety was evaluated by calculating critical temperatures and thermodynamic values, viz. TSADT, TTIT, Tb, Δ S≠, Δ H≠ and Δ G≠. The results reveal that (I) exhibits good thermal safety compared to other ion salts of 3,6-bis[(1 H-1,2,3,4-tetrazol-5-yl)amino]-1,2,4,5-tetrazine (BTATz). [ABSTRACT FROM AUTHOR]

The MxHy (AO4)z acid salts (M = Cs, Rb, K, Na, Li, NH4; A = S, Se, As, P) exhibit ferroelectric properties. The solid acids have low conductivity values and are of interest with regard to their thermal properties and proton conductivity. The crystal structure of caesium dihydrogen orthophosphate monohydrogen orthophosphate dihydrate, Cs3 (H1.5PO4)2·2H2O, has been solved. The compound crystallizes in the space group Pbca and forms a structure with strong hydrogen bonds connecting phosphate tetrahedra that agrees well with the IR spectra. The dehydration of Cs3 (H1.5PO4)2·2H2O with the loss of two water molecules occurs at 348-433 K. Anhydrous Cs3(H1.5PO4)2 is stable up to 548 K and is then converted completely into caesium pyrophosphate (Cs4P2O7) and CsPO3. Anhydrous Cs3(H1.5PO4)2 crystallizes in the monoclinic C2 space group, with the unit-cell parameters a = 11.1693 (4), b = 6.4682 (2), c = 7.7442 (3) Å and β = 71.822 (2)°. The conductivities of both compounds have been measured. In contrast to crystal hydrate Cs3 (H1.5 PO4)2·2H2O, the dehydrated form has rather low conductivity values of ~6 × 10-6 -10-8 S cm-1 at 373-493 K, with an activation energy of 0.91 eV. [ABSTRACT FROM AUTHOR]