Solid Compounds Research Articles

Structural, morphological and capacitive features of [(Pb0.5Bi0.25Y0.25) (Fe0.5Ti0.5)O3] solid state system

In the present assessment the Yttrium doped solid solution of BiFeO 3 and PbTiO 3 has been formed using solid state chemical itinerary. The structural, morphological and capacitive feature of single phase [(Pb 0.5 Bi 0.25 Y 0.25 ) (Fe 0.5 Ti 0.5 )O 3 ] solid state system has been detail studied to understand the capacitive properties. The primary study of XRD investigation affirms the solid state compound shows tetragonal structure. The non-uniform but non-void grains are spread on the surface of the material which is imitated from the SEM analysis. The substitution of small amount of Yttrium to BFO-PT solution enhances the dielectric constant as well as reduces the tangent loss or electrical leakage which is studied from temperature and frequency response of corresponding electrical parameter of the material. Due to the above important characteristics the promising material may be stand as a contender for development of different electronic perceiving device.

Ball milling: a simple and efficient method for quantitative solvent-free synthesis of new potential bioactive Ni(II) and Co(II) complexes

ABSTRCT A simple and efficient technique for quantitative solvent-free synthesis of Ni (II) and Co (II) complexes by using ball milling as a green strategy is studied. The isolated solid compounds will be characterized using micro-analytical, thermo-gravimetric, magnetic and spectroscopic studies. Theoretical studies were carried out by applying DFT theory to predict the optimized configuration for all isolated solid complexes. Moreover, the in vitro antimicrobial activity assay versus fungi and bacteria via MIC technique has higher potency of Ni (II) than Co (II). The in vitro cytotoxicity of human muscle rhabdomyosarcoma (RD) via MTT technique and the antioxidant by DPPH free radical scavenging has higher inhibitory effect on complexes than free ligand. The cyclic voltammetry of Co(II) in absence/presence of H2BHNH was investigated to realize the significant effect of complex formation on the electrochemical manners of Co(II).

A review on the challenges in machining of ceramics

Ceramics are solid compounds largely consisting of inorganic and non-metallic components bound by strong ionic and/or covalent bonds. Advanced ceramics such as Zirconia, Silicon carbide, Alumina and Silicon Nitride, find extensive applications in the field of aerospace, military and defence industry due to their enhanced mechanical and physical properties such as excellent refractoriness, high compressive strength, chemical inertness and hardness. While such properties are highly desirable in extreme environments, the inherent high brittleness and low shear strength poses a significant challenge to their machinability. Machining of ceramics is also plagued by surface damage, excessive tool wear, and edge chipping when machined using conventional techniques; non-conventional techniques such as Electric Discharge Machining (EDM) and Abrasive Water Jet machining are characterized by poor surface finish and excessive occurrence of pits, respectively. Achieving dimensional accuracy and minimizing collateral damage such as surface cracks are the key challenges in the machining of ceramics. In this review work, the machining parameters significantly influencing the machining of ceramics using non-conventional processes such as, Ultrasonic machining and Laser machining have been discussed. In contact type of non-conventional machining, feed rate significantly affects the surface finish while in the non-contact type laser scan speed seems to be deciding input parameter in machining ceramics. Rotary Ultrasonic Machining and Laser Assisted Machining (LAM) seem to be the most popular techniques for machining of ceramics, mainly due to better metal removal rate and almost defect-free surface compared to the conventional machining processes.

Development and Optimization of Tin/Flux Mixture for Direct Tinning and Interfacial Bonding in Aluminum/Steel Bimetallic Compound Casting.

Interfacial bonding highly affects the quality of bimetallic bearing materials, which primarily depend upon the surface quality of a solid metal substrate in liquid–solid compound casting. In many cases, an intermediate thin metallic layer is deposited on the solid substrate before depositing the liquid metal, which improves the interfacial bonding of the opposing materials. The present work aims to develop and optimize the tinning process of a solid carbon steel substrate after incorporating flux constituents with the tin powder. Five ratios of tin-to-flux—i.e., 1:1, 1:5, 1:10, 1:15, and 1:20—were used for tinning process of carbon steel solid substrate. Furthermore, the effect of volume ratios of liquid Al-based bearing alloy to solid steel substrate were also varied—i.e., 5:1, 6.5:1 and 8.5:1—to optimize the microstructural and mechanical performance, which were evaluated by interfacial microstructural investigation, bonding area determination, hardness and interfacial strength measurements. It was found that a tin-to-flux ratio of 1:10 offered the optimum performance in AlSn12Si4Cu1/steel bimetallic materials, showing a homogenous and continuous interfacial layer structure, while tinned steels using other percentages showed discontinuous and thin layers, as in 1:5 and 1:15, respectively. Furthermore, bimetallic interfacial bonding area and hardness increased by increasing the volume ratio of liquid Al alloy to solid steel substrate. A complete interface bonding area was achieved by using the volume ratio of liquid Al alloy to solid steel substrate of ≥8.5.

MANUFACTURING OF ACTIVATED CARBON USING DISPOSABLE COCONUT SHELLS FOR CATALYTIC ACTIVITIES AND WATER TREATMENT UTILIZATIONS

Activated carbon is a black color solid compound which is fabricated using naturally occurring materials such as woods and species of coal that composed of the majority in carbon. The activated carbon is highly remarkable compound in the catalytic activities in most of chemical industries and water treatment activities because of the significant performances of such activated carbon due to the sufficiency of the surface property which is called as the adsorption with the couple of high porosity. The manufacturing of activated carbon from disposable coconut shells and the investigations of the physic-chemical characteristics of such activated carbon were the expectances of the existing research. Domestically collected coconut shells were burnt in the range of different temperatures 390°C–300°C after removing unnecessary constituents. The chemical composition of the powdered activated carbon was inspected using an X-ray fluorescence (XRF) spectrophotometer and the surfaces of prepared activated carbon were examined using an optical microscope. As the outcomes of the above experiments, it seems that the most adequate burning temperature for the manufacturing of that batch of coconut shells was in the range of 330°C–350°C, 68.85% of ferrous and 31.15% of potassium as the composed metallic element apart from the non metallic carbon and the pure black color non- composite surfaces were observed under the microscopic studies. It is encouraged to develop this production using cost effective materials such as the shells of fesults which are belonging to the palm cast while utilizing the productions through the various applications in chemical industries

Multi-functional materials based on α-cyanostilbene: Response to mechanical stimuli and selective detection of PNA

Two α-cyanostilbene derivatives NCS1 and NCS2 were designed and synthesized. Both two compounds exhibited AIE properties. Solid compounds showed excellent mechanochromism with 29/26 nm redshift and distinct acid-base vapor chromotropism, which could be applied for relevant sensors. XRSD and PXRD spectra revealed the intrinsic relationship between mechanochromism and molecular packing mode. The twisted molecular conformation became more planar with an increase in conjugation after grinding, resulting in the redshift in fluorescence spectra. Moreover, the emission spectra of NCSs showed obvious fluorescence quenching for p-nitroaniline (PNA) with excellent selectivity. The fluorescence intensity showed better linear relationship at low concentration of PNA. The limit of detections were as low as 0.42 μmol L−1 and 0.60 μmol L−1, respectively. DFT theory proved that this sensing mechanism was attributed to the process of photoinduced electron transfer (PET). Importantly, NCSs were successfully used for PNA detection in real environments. We provide the working basis for developing high-performance multi-functional materials.

Planetary Refractory Composition and Volatile Accretion into Gas Giants in the Protoplanetary Disks of the Sun and WASP-12

Abstract We present a detailed theoretical exploration of the refractory compositions and volatile enrichments of planets forming in protoplanetary disks with solar-like conditions. The two cases of the Sun and WASP-12 are studied due to the availability of spectral measurements and their known planets. The distribution throughout their disks of solid compounds with a wide range of volatilities is computed by a comprehensive chemical thermodynamics code. After the calculation of refractory compounds down to the water snowline, the compositional distributions are documented for planets generated in certain locations of protoplanetary disks depending on thermodynamic conditions. These results are referred to proposed bulk compositions for solar terrestrial planets, and for the core of the hot Jupiter WASP-12b. The material left over after the formation of rocky components is collected and treated in calculations to determine the abundances of fundamental volatile molecules in the outer regions of the disks. The distributions of planetesimal volatile composition are then altered for four different cases of the carbon-to-oxygen ratios, and for oxidizing and reducing conditions, in order to adjust the best fit for the accretion zone of Jupiter and WASP-12b. We compare the Jovian results to in situ atmospheric measurements from Jupiter’s atmosphere. Overall, this study proposes a holistic approach to estimate possible planetary interior and envelope compositions from hot toward cold disk zones, along with the mass of planetesimals accreted into the envelopes of gas giants.

DFT/TDDFT studies of the structural, electronic and NBO properties of some complexes with the tetrathiafulvalene-1,3-benzothiazole ligand

In this work, the electronic structures and derived properties (UV, NBO and more) of the three know and relevant Cu-based complexes of tetrathiafulvalene (TTF) are reported. The experimentally available structures of formulas [Cu(hfac)2(L)2]0,2+ and [Cu(L)2]2+ (L = TTF-1,3-benzothiazole and hfac = hexafluoroacetylacetonate are characterized by variable π-π stacking in the crystals. Since the latter depends on the spin unpairing at the TTF portions of L, we have optimized with the DFT method the single units as potential building blocks of the solid state compounds. The geometric parameters appear to be in a satisfactory agreement with the available experimental data and, by taking into account the various spin distributions (possible ground states), we analyzed the corresponding MO features. The APT atomic charges were evaluated and the coordination bond strengths were evaluated by the Natural Bond Orbital (NBO) analysis, which also confirmed the π electron delocalization at the TTF portion of L. The theoretical UV–visible spectra, computed with the time-dependent DFT/TDDFT method, show that the charge transfer bands in all complexes are red-shifted with respect to the corresponding free ligand.

Direct Electrochemical Hydrogenation of Naphthalene to Decalin at Pt and Pt-Ru Alloy Electrodes in Liquid Phase

Decalin has been recognized as one of organic chemical hydrides, which can be obtained by reversible hydrogenation reaction of naphthalene in the presence of a catalyst. However, because naphthalene is solid under the ambient conditions, the naphthalene/decalin system has been hardly turned to practical use for the hydrogen storage so far. Recently, we have, for the first time, demonstrated a direct electrochemical hydrogenation of toluene to methylcylcohexane at Pt electrodes in a microemulsion solution at room temperature [1]. In a microemulsion system, a hydrophobic organic compound and water (or hydrated ion, e.g. proton) can be supplied simultaneously to an electrode surface, and can react together with electron transfers. Thus, any solid organic compounds that form a microemulsion solution with water can react electrochemically with proton at lower temperatures than their melting or boiling points. In the present study, direct electrochemical hydrogenation of naphthalene was investigated by employing the microemulsion technique with Pt and Pt-Ru electrocatalysts sputtered on a Ti sheet. Author has, for the first time, achieved a high Faraday efficiency and selectivity for the naphthalene/decalin conversion under a galvanostatic condition at 60°C.Thin Pt-Ru alloy or pure Pt were prepared on a Ti sheet by RF-sputtering a Pt target with or without Ru target. The composition of the alloys was controlling by varying exposed target area ratio, and analyzed by X-ray photoelectron spectroscopy. Microemulsion electrolytes were prepared from naphthalene, a sulfuric acid solution and two surfactants by mixing and sonicating. All the electrochemical measurements were performed with an H type cell at 60°C. A platinum black and a reversible hydrogen electrode were employed as the counter electrode and reference electrode, respectively. The working electrode was immersed into a microemulsion solution while the counter electrode into a sulfuric acid solution. After the electrolysis, products were analyzed and quantified by gas chromatography (GC) with a flame ionization detector for calculating the Faraday efficiency and selectivity. Toluene was employed as internal standard for quantitative GC analysis.Fig. 1 shows cyclic voltammograms (CVs) at a Pt/Ti electrode taken in 1 M sulfuric acid (black) and a naphthalene-containing microemulsion electrolyte (red) at sweep rate of 1 mV/s. In the sulfuric acid solution, the Pt/Ti electrode exhibited a characteristic reversible hydrogen adsorption wave below 0.3 V. In contrast, the hydrogen adsorption feature completely disappeared from the CV in the microemulsion electrolyte presumably due to an adsorption of naphthalene on the Pt surface. However, reduction current appeared below ca. 0.2 V and steeply increased below 0.05 V. This can be explained by a partial reduction and desorption of the adsorbed naphthalene molecules[2] and subsequent bulk hydrogenation reaction on the vacant sites. It should be pointed out that the steep reduction current was observed at more positive potential than the hydrogen evolution reaction, suggesting a Langmuir-Hinshelwood type reaction with underpotential-deposition (UPD) hydrogen on the electrode surface.The GC analysis after a constant-current electrolysis at 2 mA cm-2 for 150 min revealed the formation of cis- and trans- decalin via10-electron transfer as well as tetralin via 4-electron transfer. In comparison between the isomers, cis-decalin was the dominant species presumably due to a flat orientation of the adsorbed naphthalene molecule [2], which reacted with UPD hydrogens via the Langmuir-Hinshelwood type mechanism. Surprisingly, the Fraday efficiency for the naphthalene/decalin conversion and selectivity for dacalin/tetralin was much improved at a Pt-Ru/Ti electrode, up to 48% and 93%, respectively. These improvements might be ascribed to change in the adsorption energy of naphthalene on the Pt site due to alloying with Ru, or change in the adsorption site to Ru.Reference[1] M. Wakisaka and M. Kunitake, Electrochem. Commun. 64 (2016) 5.[2] S.-L. Yau, Y-G. Kim, and K. Itaya, J. Phys. Chem. B 101 (1997) 3547. Figure 1

The effect of ultrasound treatment on the efficiency of membrane clarification of carrot juice

Large particles in carrot juice create a turbid appearance; therefore, membrane treatment can be used to clarify it. To evaluate the effect of ultrasound on the membrane processing efficiency, ultrasound (1,000 W, 20 kHz) was applied to carrot juice and membrane unit. Results showed that this process can increase the permeate flux by about 10–3 kg/m2s, and the rate of the increased flux caused by the ultrasound increases with increasing transmembrane pressure and feed flow rate; as, the best performance was achieved in 1 bar and 15 ml/s. Also, cake formation is the main fouling mechanism in the whole process. The total soluble solid content, pH and total phenolic compounds did not change during clarification. But, antioxidant activity (55%), total titratable acidity (47.5%), β-Carotene (59.2%) and turbidity (97.9%) were decreased. It can concluded that ultrasound can increase the efficiency of membrane processing of carrot juice due to reduce total membrane resistance. Practical applications In this study, ultrasound was applied in the membrane clarification of carrot juice, as one of the newest methods to reduce membrane fouling. The practical application of this study is that by using the cavitation phenomenon and the stress caused by the explosion of the bubbles created in this phenomenon, the large particles of the juice become smaller particles. In addition, this technology breaks down the cake on the membrane, which increases the efficiency of the membrane. This method can be used in most factories, especially in the food industry, when producing fruit juice.

Spotlight on Alkali Metals: The Structural Chemistry of Alkali Metal Thallides

Alkali metal thallides go back to the investigative works of Eduard Zintl about base metals in negative oxidation states. In 1932, he described the crystal structure of NaTl as the first representative for this class of compounds. Since then, a bunch of versatile crystal structures has been reported for thallium as electronegative element in intermetallic solid state compounds. For combinations of thallium with alkali metals as electropositive counterparts, a broad range of different unique structure types has been observed. Interestingly, various thallium substructures at the same or very similar valence electron concentration (VEC) are obtained. This in return emphasizes that the role of the alkali metals on structure formation goes far beyond ancillary filling atoms, which are present only due to charge balancing reasons. In this review, the alkali metals are in focus and the local surroundings of the latter are discussed in terms of their crystallographic sites in the corresponding crystal structures.

Noble Gases in Solid Compounds Show a Rich Display of Chemistry With Enough Pressure.

In this review, we summarize the rapid progress that has been made in the study of noble gas chemistry in solid compounds under high pressure. Thanks to the recent development of first-principles crystal structure search methods, many new noble gas compounds have been predicted and some have been synthesized. Strikingly, almost all types of chemical roles and interactions are found or predicted in these high-pressure noble gas compounds, ranging from cationic and anionic noble gases to covalent bonds between noble gas atoms, and to hydrogen bond-like noble gas bonds. Besides, the recently discovered He insertion reactions reveal a unique chemical force that displays no local chemical bonding, providing evidence that research into noble gas reactions can advance the frontier of chemistry at the very basic level.

Solid Acid Electrochemical Cell for the Production of Hydrogen from Ammonia

Summary Production of high-purity hydrogen by thermal-electrochemical decomposition of ammonia at an intermediate temperature of 250°C is demonstrated. The process is enabled by use of a solid-acid-based electrochemical cell (SAEC) in combination with a bilayered anode, comprising a thermal-cracking catalyst layer and a hydrogen electrooxidation catalyst layer. Cs-promoted Ru on carbon nanotubes (Ru/CNT) serves as the thermal decomposition catalyst, and Pt on carbon black mixed with CsH2PO4 is used to catalyze hydrogen electrooxidation. Cells were operated at 250°C with humidified dilute ammonia supplied to the anode and humidified hydrogen supplied to the counter electrode. A current density of 435 mA/cm2 was achieved at a potential of 0.4 V and ammonia flow rate of 30 sccm. With a demonstrated faradic efficiency for hydrogen production of 100%, the process yields hydrogen at a rate of 1.48 m o l H 2 / g c a t h .

Development and Evaluation of Thermodynamic Models for Predicting Cold Flow Properties of Biodiesel

Biodiesel, especially palm oil-based methyl esters (PME), is steadily increasing in consumption in Indonesia and Malaysia as a petroleum diesel substitute. PME has poor cold flow properties due to the presence of saturated bound glycerols. Bound glycerols, such as monoglycerides (MAGs), diglycerides (DAGs), and triglycerides (TAGs), are impurities in biodiesel as a result of incomplete transesterification, and have high melting points. These minor components often solidify even at temperatures higher than the cloud point and thus cause clogging in fuel filters. It is, therefore, essential to predict the solidification temperature for the application of biodiesel, particularly in high blending levels. This study developed and evaluated thermodynamic models for predicting the solidification of biodiesel. Binary and multicomponent mixtures of fatty acid methyl esters (FAMEs) and bound glycerols were prepared as biodiesel models. The solidification temperature was measured by differential scanning calorimetry and the results were compared with the predicted values. It was discovered that most of the binary mixtures of a FAME and a bound glycerol (MAG, DAG, or TAG) behaved as eutectic systems, in which a solid phase consists of a single component. In the case of the eutectic system, the solidification temperature could be estimated by assuming non-ideal liquid solutions, and the modified UNIFAC (Dortmund) model helped calculate the activity coefficient. However, the mixtures of MAG/MAG differed from the eutectic system, suggesting that the solid compounds of different types of MAGs were formed. Thus, the compound formation model was developed, which was successful in predicting the solidification temperatures of biodiesel model fuels that consist of several kinds of FAMEs and MAGs.

Effect of laser remelting on microstructure and properties of two Ni-base coatings by supersonic particles deposition

Remelting treatment of In718 and In625 coatings deposited by supersonic particles were conducted by using laser technology. The microstructure, phase composition, microhardness, wear resistance and corrosion of the coating before and after remelting were studied. The results showed that defects such as voids and cracks of the deposited coating were eliminated by laser remelting treatment, the microstructure of the coating became compact and uniform and the bonding mode changed from mechanical bonding to metallurgical bonding. The deposited coating consisted of γ-Ni solid solution and Fe3Ni2 intermetallic compound phase, remelting to form a new phase Ni3(Al,Ti) and high hard phase carbide (Nb,Mo) C. The average microhardness of the remelted coating was 6.96 GPa, which was 1.72 times than that of the deposited coating. The wear resistance of remelting coating was significantly better than that of deposited coating and substrate, and its wear form was mainly abrasive wear. The corrosion resistance of the coating was significantly improved after remelting treatment.

Prospects for the use of liquid waste from the production of sodium carbonate as a coolant based on the ternary system CaCl2-K2Cr2O7-H2O

Currently, the urgent problem is the secondary use of distillation liquid - a waste product from the production of sodium carbonate, which is an aqueous solution containing about 10 % calcium chloride and a small amount of other salts. It is proposed to use a solution based on a distiller liquid as a coolant in a heat exchange system in the production of soda. The introduction of potassium dichromate into the system creates an inhibitory effect and prevents pipe corrosion. To study phase equilibria in the CaCl2 - K2Cr2O7 - H2O system, state diagrams were constructed at temperatures of 20, 3, and -7°C. With decreasing temperature, the homogeneous region noticeably decreases and shifts to the CaCl2 - H2O axis. The eutectic point is limited to a very narrow area in which the weight fraction of potassium dichromate does not exceed 3%.Using the Skrynemakers method, it was found that in a region with a calcium chloride content of less than 40 %, potassium dichromate crystallizes. For the region adjacent to the apex of calcium chloride, it is impossible to establish the composition of the solid phase and the boundaries of its crystallization using the Skrynemakers method. This is due to the fact that the binary system CaCl2 - K2Cr2O7 is a ternary reciprocal system K +, Ca2 + Cl-, Cr2O72- . In this area, the formation of solid solutions or compounds based on the binary system K2Cr2O7 - CaCr2O7 is supposed. For the temperature range from -7 ?С to 50 ?С, the refrigerant composition was proposed: 3 % K2Cr2O7 - 10.2 % CaCl2 - 86.8 % H2O. In the temperature range from 20 ?С to 60 ?С, the composition of the solution is: 6 % K2Cr2O7 – 10 % CaCl2 – 84 % H2O.

High energy density materials based on fluorinated bridged trinitromethyl azo triazole derivatives: a quantum chemical study of thermodynamic and energetic properties

High energy density materials (HEDM) have gained extensive attention due to their energetic properties and safety issues. Nitro and fluoro groups, among others, have become viable substituents on the triazole framework because of their particular contribution to detonation properties and moderate sensitivity. In this study, Density Function Theory (DFT) approach was employed to design fluorinated bis(trinitromethyl) azo triazoles. The molecular structures, thermodynamic properties of gaseous species (e.g., enthalpies of detonation and enthalpies of formation) and energetic properties of solid materials (detonation heat Q, pressure PD and velocity VD) have been investigated. The best characteristics attained for the designed azo fluorinated solid compounds are as follows: Q 1650–1690 cal g−1, PD 44–46 GPa and VD 9.8 km s−1. These characteristics are superior to those of conventional explosives, indicating that fluorinated bis(trinitromethyl) azo triazoles are promising HEDM.

Computationally Predicted High-Throughput Free-Energy Phase Diagrams for the Discovery of Solid-State Hydrogen Storage Reactions.

The design of multinary solid-state material systems that undergo reversible phase changes via changes in temperature and pressure provides a potential means of safely storing hydrogen. However, fully mapping the stabilities of known or newly targeted compounds relative to competing phases at reaction conditions has previously required many stringent experiments or computationally demanding calculations of each compound's change in Gibbs energy with respect to temperature, G(T). In this work, we have extended the approach of constructing chemical potential phase diagrams based on ΔGf(T) to enable the analysis of phase stability at non-zero temperatures. We first performed density functional theory calculations to compute the formation enthalpies of binary, ternary, and quaternary compounds within several compositional spaces of current interest for solid-state hydrogen storage. Temperature effects on solid compound stability were then accounted for using our recently introduced machine learned descriptor for the temperature-dependent contribution Gδ(T) to the Gibbs energy G(T). From these Gibbs energies, we evaluated each compound's stability relative to competing compounds over a wide range of conditions and show using chemical potential and composition phase diagrams that the predicted stable phases and H2 release reactions are consistent with experimental observations. This demonstrates that our approach rapidly computes the thermochemistry of hydrogen release reactions for compounds at sufficiently high accuracy relative to experiment to provide a powerful framework for analyzing hydrogen storage materials. This framework based on G(T) enables the accelerated discovery of active materials for a variety of technologies that rely on solid-state reactions involving these materials.

The Structure and Thermal Properties of Solid Ternary Compounds Forming with Ca2+, Al3+ and Heptagluconate Ions.

In the present work, the structure and thermal stability of Ca–Al mixed-metal compounds, relevant in the Bayer process as intermediates, have been investigated. X-ray diffraction (XRD) measurements revealed the amorphous morphology of the compounds, which was corroborated by SEM-EDX measurements. The results of ICP-OES and UV-Vis experiments suggested the formation of three possible ternary calcium aluminum heptagluconate (Ca-Al-Hpgl) compounds, with the formulae of CaAlHpgl(OH)40, Ca2AlHpgl2(OH)50 and Ca3Al2Hpgl3(OH)90. Additional IR and Raman experiments revealed the centrally symmetric arrangement of heptagluconate around the metal ion. The increased thermal stability was demonstrated by thermal analysis of the solids and confirmed our findings.

Structural Expansion of Chalcogenido Tetrelates in Ionic Liquids by Incorporation of Sulfido Antimonate Units.

Multinary chalcogenido (semi)metalate salts exhibit finely tunable optical properties based on the combination of metal and chalcogenide ions in their polyanionic substructure. Here, we present the structural expansion of chalcogenido germanate(IV) or stannate(IV) architectures with SbIII, which clearly affects the vibrational and optical absorption properties of the solid compounds. For the synthesis of the title compounds, [K4(H2O)4][Ge4S10] or [K4(H2O)4][SnS4] were reacted with SbCl3 under ionothermal conditions in imidazolium‐based ionic liquids. Salt metathesis at relatively low temperatures (120 °C or 150 °C) enabled the incorporation of (formally) Sb3+ ions into the anionic substructure of the precursors, and their modification to form (Cat)16[Ge2Sb2S7]6[GeS4] (1) and (Cat)6[Sn10O4S20][Sb3S4]2 (2 a and 2 b), wherein Cat=(C4C1C1Im)+ (1 and 2 a) or (C4C1C2Im)+ (2 b). In 1, germanium and antimony atoms are combined to form a rare noradamantane‐type ternary molecular anion, six of which surround an {GeS4} unit in a highly symmetric secondary structure, and finally crystallize in a diamond‐like superstructure. In 2, supertetrahedral oxo‐sulfido stannate clusters are generated, as known from the ionothermal treatment of the stannate precursor alone, yet, linked here into unprecedented one‐dimensional strands with {Sb3S4} units as linkers. We discuss the single‐crystal structures of these uncommon salts of ternary and quaternary chalcogenido (semi)metalate anions, as well as their Raman and UV‐visible spectra.