Crystal Powder Research Articles

Application of Ni-based superalloy in aero turbine blade: A review

A superalloy is a high-performance alloy used for achieving stability and strength at elevated temperatures. Generally, a temperature of about 800°C is developed at the first stage of the aero turbine blade. So it is a challenge to choose a material that can withstand such high temperatures. Nowadays advanced generation single crystal Ni-based superalloys are being used for the fulfillment of high-temperature requirements in aero turbine components. But the continuous effort is being carried out to manufacture new materials that can withstand more and more temperatures generated at aero turbine because the high-temperature operation of the turbine is directly proportional to the efficiency of a turbine engine. The requirement of high-temperature application upgraded the Ni-based superalloy and different generations of alloys were prepared from time to time those were discussed in the paper. Recent developments of superalloys in the paper mainly include fifth and sixth generations of superalloys those incorporate Hf, Re, and Ru-like elements in significant amounts. A brief extension discussion has been placed on the types, processing, and hot deformation characteristics of Ni-based superalloys. VIM melting, single crystal growth, directional solidification, and powder metallurgy techniques for manufacturing Ni-based superalloys are discussed in detail. The strengthening mechanism and machinability behavior depict the characteristics of superalloys in a mechanical direction. Heat treatment and hot deformation behavior of Ni-based superalloy was precisely discussed in the context so as to correlate the strength of the material with the temperature change. Overall, the paper describes the origin, processing and characteristics of Nickel based superalloy in detail.

Unveiling the optical, thermal and nonlinear behavior of guanidinium benzenesulfonate: A promising organic single crystal for NLO applications

Organic crystals have aroused significant interest in the nonlinear optical field due to the presence of higher order nonlinearity. This article enlightens about the growth, structural, optical, thermal and nonlinear optical (NLO) characteristics of guanidinium benzenesulfonate (GBS) single crystal for NLO applications. Herein, we employed slow evaporation solution technique (SEST) to grow good quality crystals of GBS. The single crystal X-ray diffraction & powder XRD were performed in order to study the crystal structure. The functional groups in the GBS molecule were analysed using the qualitative FT-IR spectra. The transmittance and optical bandgap of titled crystal were assessed by UV–Visible spectroscopy. The sample was excited at a wavelength 260 nm to see its emission spectrum through PL spectroscopy. A decrease in LDT value was observed with increase in the pulse repetition rate using Nd:YAG laser. TG-DTA curve were assessed at different rates of heating to examine the thermal stability of the titled material. The activation energy was calculated by using thermogravimetric data. To investigate third order nonlinearity of grown crystal, the NLO coefficients were estimated by adopting well known Z-scan technique equipped with a Ti:sapphire based laser oscillator.

Investigating the molecular crystals of L-Alanine, DL-Alanine, β-Alanine, and Alanine hydrogen chloride: Experimental and DFT analysis of structural and optoelectronic properties

In this study, DFT calculations were employed to assess and contrast the structural, electronic, and optical characteristics of five alanine crystal forms. The Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA) with the Tkatchenko-Scheffler dispersion correction scheme was employed and compared to the PBE functional and the local density approximation (LDA) without dispersion correction. Experimentally, alanine crystal powders were characterized through X-ray diffraction (XRD) and UV–VIS absorption spectrum. Additionally, UV–VIS absorption measurements were performed on L-α-alanine, DL-alanine, β-alanine, and alanine hydrochloride solvated in water. Significant deviations (>10%) were observed between the experimental crystal lattice parameters and those predicted by the GGA and LDA methods. Incorporating dispersion correction into the GGA functional improved prediction accuracy. Additionally, time-dependent DFT (TD-DFT) computations using the polarizable continuum model were conducted to analyze the UV/VIS absorption spectrum of α-, β-, DL-, and hydrogen chloride alanine in water and interpret experimental data. Different alanine crystals exhibited substantial anisotropic electronic and optical properties, including effective masses, absorption, and dielectric function. The L-α-HCl structure displayed the smallest band gap (4.67 eV), suggesting its suitability for applications such as L-α/L-α-HCl/L-α quantum well structures. The main effective masses of electrons and holes were also determined for each crystal for a better understanding of their electronic transport properties.

Assembly of two luminescent cadmium(II) 4,4'-phosphini Co-dibenzoate coordination polymers

Two new cadmium(II) coordination polymers [Cd(HL)(H2O)]·1.5H2O (1) and [Cd(HL)(4-bpmp)0.5]·2H2O (2) (H3L = 4,4'-phosphinicobis-dibenzoic acid, and 4-bpmp = N,N'-bis(4-pyridylmethyl)piperazine) have been synthesized by self-assembly of CdCl2 with 4,4'-phosphinicobis-dibenzoate, and N,N'-bis(4-pyridylmethyl)piperazine through solvothermal/hydrothermal method. Their structures were confirmed by X-ray single crystal diffraction, infrared spectrometer (IR), and powder X-ray diffraction (PXRD) and TGA techniques. Both compounds are in Pī space group and exhibited a 2D networks constructed from dinuclear [Cd2(POO)2] or paddle-wheel [Cd2(COO)2(POO)2] units, respectively. In 2, the Cd2+ is five-coordinated and shows a rare tetragonal pyramidal geometry. At room temperature, the compounds exhibit moderately intense blue and green fluorescence emission with peaks at 381 nm and 509 nm, respectively.
 KEY WORDS: Cadmium(II) compounds, Photoluminescence, Carboxyphosphinate ligand
 Bull. Chem. Soc. Ethiop. 2024, 38(1), 85-98. DOI: https://dx.doi.org/10.4314/bcse.v38i1.7

Hydrothermal and Mechanosynthesis of Mixed‐Cation Double Perovskite Scintillators for Radiation Detection

AbstractThis article details work performed on the synthesis and characterization of an inorganic mixed‐cation double halide perovskite, Cs2Ag.6Na.4In.85Bi.15Cl6 (CANIBIC). Single crystals have been created via a hydrothermal reaction, milled into a powder, and pressed into pellets, while nanocrystals have been directly synthesized via mechanosynthesis. A computational model is constructed to predict the X‐ray diffraction pattern of CANIBIC; this model aligns very well with the X‐ray diffraction pattern measured for CANIBIC crystal powder. This model can therefore be developed in the future as a tool to predict lattice parameters and crystal structures of other novel double‐halide perovskites. Photoluminescence spectra obtained from each format show broad emission centered at 630 nm, as is typical for self‐trapped exciton emission; self‐trapped exciton emission is also confirmed by investigating photoluminescence intensity as a function of laser power. Nanocomposites are produced via the loading of nanocrystals of CANIBIC into PMMA. Although nanocomposite disks consisting of a small proportion of CANIBIC nanocrystals in PMMA have a smaller mass attenuation coefficient than a pressed pellet of CANIBIC, these disks have comparatively bright radioluminescence due to their optical transparency. These nanocomposite disks are therefore a particularly useful format for the practical use of the CANIBIC scintillator.

A significantly fluorescence-enhanced probe for Al3+ based on a new AIEgens Mn-based metal-organic frameworks

Photoluminescence chemical sensors based on metal-organic frameworks have excellent applications in detecting heavy metal ions in water systems due to their advantages such as good sensitivity and short response time. Herein, a novel AIEgens Mn-based LMOF, [Mn(tipe)4(bpdc)2]n (LMOF-1) (tipe = 1,1,2,2-tetrakis(4-(1H-imidazol-1-yl)phenyl)ethene, bpdc = [1,1′-biphenyl]-4,4′-dicarboxylic acid), was synthesized by solvothermal method, and characterized by X-ray single crystal diffraction, elemental analysis and powder X-ray diffraction. Suprisingly, LMOF-1 has good stability in water and shows high selectivity and sensitivity in detecting Al3+ by significantly fluorescence-enhanced phenomenon with its LOD at 1.77×10−7M, which can meet the World Health Organization (WHO) standard for detecting Al3+ in drinking water. This work provides insights into the potential applications of Mn-based MOFs in chemical sensing.

Structure, fluorescence and energy transfer of 2D multinuclear-LnIII-incorporated organic–inorganic hybrid arsenotungstates

A family of isostructural 2D multinuclear LnIII-incorporated organic–inorganic hybrid arsenotungstates were fleetly synthesized, denoted as K4[{Ln(H2O)7}2 {As4W44O143(OH)8(H2O)6(DL-ala)2}{Ln2(H2O)4(DL-ala)}2]‧54H2O (Ln=Sm (1), Eu (2), Gd (3)), containing a centrosymmetric polyanion [{As4W44O143(OH)8(H2O)6(DL-ala)2}{Ln2(H2O)4(DL-ala)}2]8–. The polyanion is constituted of two {As2W19O62(OH)2(H2O)3}6– building blocks encapsulating a deca-nuclear Ln-W heterometallic cluster [W6O21(OH)4(DL-ala)2{Ln2(H2O)4(DL-ala)}2]6–. Obtained compounds were characterized by means of elemental chemical analysis, thermogravimetric, single crystal X-ray and powder diffraction and FT-IR studies. The optical band-gaps of 1 and 2 are 3.05 eV and 3.09 eV, respectively, according to the UV–Vis diffuse reflectance. In addition, 1 and 2 demonstrate the solid-state fluorescence performance (1: orange, 2: red), of which the POMs chromophore can be considered as an antenna ligand to improve luminescence efficiency of LnIII centers via energy migration.

Design and Analysis of POM‐Guanidine Compounds: Achieving Ultra‐High Single‐Crystal Proton Conduction

AbstractThe “visible” proton‐conducting pathway offers a distinct advantage for researching the mechanism of proton conducting materials at the molecular level and developing new materials. To achieve this, three crystalline materials are constructed via acid–base chemistry based on phosphomolybdic acid and diversfied guanidine, namely, (CN3H6)6(PMo12O40)2·H2O (GH–PMo12), (CN4H7)3(PMo12O40)·H2O (AGH–PMo12), and (CN5H8)3(PMo12O40)·3.5H2O (DAGH–PMo12). Proton conductivity of GH–PMo12 in the [001] direction reaches up to 0.19 S cm−1 at 85 °C and 98% RH, as elucidated by impedance studies of single crystals. The clear proton transport path is proposed through the analysis of single crystal structure. Moreover, impedance studies of powder crystals reveal that the proton conductivity of GH–PMo12 is higher than that of the other two compounds. The underlying reasons for this result are clarified through the analysis of the pKa, proton density, and spatial structure. Additionally, GH–PMo12 is fabricated into composite membrane with a peak proton conductivity of 5.31 × 10−2 S cm−1, which exhibits promising potential for real‐world applications.

Crystal structure and X-ray powder diffraction data for Lumateperone tosylate

X-ray powder diffraction data, unit-cell parameters, and space group for the Lumateperone tosylate, C24H29FN3O⋅C7H7O3S, are reported [a = 15.5848(10) Å, b = 6.0700(4) Å, c = 31.3201(14) Å, β = 96.544(5)°, V = 2943.58 Å3, Z = 4, and space group C2]. In each case, all measured lines were indexed and were consistent with the corresponding space group. The single-crystal data of Lumateperone tosylate is also reported, respectively [a = 15.626(3) Å, b = 6.0806(10) Å, c = 31.415(5) Å, β = 96.609(7)°, V = 2965.1(8) Å3, Z = 4, and space group C2]. The experimental powder diffraction pattern has been well matched with the simulated pattern derived from the single-crystal data with preferred orientation in the [002] direction (orientation coefficient = 0.75).

Fluorescent and electronic properties of Dysprosium acylpyrazolone complexes along with their synthesis and structural features

Six distorted square antiprismatic eight coordinated Dysprosium acylpyrazolone complexes were synthesized having the compositions [Dy(L1)3(EtOH)(H2O)] (DyL1), [Dy(L2)3(EtOH)(H2O)] (DyL2), [Dy(L3)3(EtOH)(H2O)] (DyL3), [Dy(L4)3(EtOH)(H2O)] (DyL4), [Dy(L5)3(EtOH)(H2O)] (DyL5), and [Dy(L6)3(H2O)(EtOH)] (DyL6). The structure of all six complexes was examined using ESI-mass, FT-IR, UV–Vis, powder XRD, and thermogravimetric methods. According to the single crystal analysis of DyL4A, the complex was found eight coordinated (DyO8) with a distorted square antiprismatic geometry. The comparison of stimulated powder pattern of DyL4A crystal and experimental powder x-ray data helps to confirm the geometry of other complexes. In the solid-state emission spectra, the transition 4F9/2→6H13/2, which is close to the yellow region of the visible spectrum (∼510–530 nm), exhibits hypersensitivity. The variance in intensity between electric-dipole and magnetic-dipole transition suggests a less asymmetric environment. The solvent effect has been thoroughly investigated through a comparative analysis of electronic spectra in different solvents. The intensity of emission spectra, Y/B ratio, and antenna effect energy diagram were examined from solid-state emission spectra.

Stability Optimization of 0D Cs3Cu2Cl5 Single Crystal with High Green Emission for Optoelectronics

Cs3Cu2Cl5 is unstable owing to ionic migration and lattice decomposition in the atmosphere. In addition, obtaining large bulk single crystals of Cs3Cu2Cl5 is challenging. Herein, a novel strategy is proposed for synthesizing a Cs3Cu2Cl5 single crystal that exhibits excellent crystallinity and photoluminescence (PL) properties using an antisolvent‐assisted method. Na+ is doped into the Cs3Cu2Cl5 lattice to replenish the lattice defects caused by chlorine vacancies, thus leading to stronger chemical interactions between Cu+ and Cl− ions. Moreover, Na+ doping circumvents ionic migration and lattice decomposition, thereby enhancing the PL intensity and maintaining the long‐term stability of Cs3Cu2Cl5 in the atmosphere. Incorporating 10% Na+ into the Cs3Cu2Cl5 lattice enhances the PL intensity by 18%, and the high‐stability PL can maintain more than 48.5% of the PL intensity after 90 d in an atmospheric environment. In addition, a white light‐emitting device (LED) is fabricated using the 10% Na+‐doped Cs3Cu2Cl5 crystal powder and it exhibits a high color‐rendering index (93.7) and correlated color temperature (7120 K). Additionally, it exhibits superior stability, even at a high temperature of 120 °C. Thus, the excellent high‐temperature stability of Cs3Cu2Cl5 can promote its practical application in LED.

Construction of three novel Co/Zn/Cd(II) coordination polymers based on the same ligands: Different spatial structures, electrocatalysis and photoluminescence properties

Three new metal coordination polymers with different spatial structure, namely {[Co2(H2O)6(4-PDCA)2]2·3H2O}n (SNUT-12), {[Cd(H2O)2(4-PDCA)]·2H2O}n (SNUT-13) and [Zn2(4-PDCA)2]n (SNUT-14), where H2(4-PDCA) = 1-(4-carboxyphenyl)-5-methyl-4-oxo-1,4-dihydropyridazine-3-carboxylic acid, were synthesized by changing the central ion with the same ligand under solvothermal and hydrothermal conditions, which were further characterized by single crystal X-ray diffraction, powder XRD, FT-IR and TGA. Single crystal X-ray analysis revealed that SNUT-12 exhibits a 1D infinite zigzag chains which were constructed by Cobalt(II) ion and 4-PDCA2− ligand, SNUT-13 features a 2D ladder-like structure. Meanwhile, SNUT-14 displays 2-fold 3D → 3D parallel interpenetrating frameworks. In addition, SNUT-12 exhibited high electrocatalytic oxygen evolution reaction, and SNUT-13, SNUT-14 showed strong fluorescence at room temperature.

Magnetic field-induced phase transitions in Cu(en)2SO4 – A dimerized S = 1/2 quantum antiferromagnet

Magnetic susceptibility, magnetization and specific heat of powder and single crystal of Cu(en)2SO4 were investigated. The analysis of the data confirmed that Cu(en)2SO4 can be treated as a quasi-two-dimensional array of magnetic dimers with singlet-ground state persisting up to about 6.5 T. Magnetization and susceptibility studies were performed in the singlet phase and the analysis revealed that g-factor anisotropy is the main mechanism responsible for the different behavior in the magnetic field applied along the b and c axis. The investigation of powder and single crystal specific heat in magnetic fields applied along all three crystallographic directions revealed only small anisotropy associated with the g-factor anisotropy. All mentioned data sets resemble main features of the spin 1/2 HAF dimer model with J/kB = -5.52 K. The observed deviations can be ascribed to the presence of inter-dimer interactions with the effective strength z’J’/kB = -2.7 K. In fields above 6.5 T the system passes from the singlet phase to the ordered state stable up to about 11 T. The expectation of a dome shape magnetic phase diagram is based on the strong dimerization of the magnetic lattice. Future experiments and calculations are discussed to identify the origin of the quantum phase transition associated with the gap closing.

Copper(II) and Zinc(II) coordination polymers based on glutaric acid and 1,2-bis(4-pyridyl)ethylene: Hydrothermal synthesis, characterization and thermal behaviors

1,2-bis(4-pyridyl)ethylene (dpe) and glutaric acid (H2glu) with Cu(II) and Zn(II) afforded two coordination polymers namely, [Cu(µ3-glu)(µ-dpe)]n (1) and [Zn(µ3-glu)(µ-dpe)0.5]n (2), and they were characterized by elemental analysis, IR spectroscopies, single crystal X-ray diffraction and powder X-ray diffraction (PXRD) techniques. X-ray diffraction studies have shown that complex 1 crystallizes in the triclinic system, in the P-1 space group, while complex 2 crystallizes in the C2/c space group in the monoclinic system. In complexes 1 and 2, the glu ligand adopts tetradentate coordination mode that one carboxylate group bidentate, other carboxylate group bis(monodentate)-bridging. Complex 1 displayed 2D network with {44.62} point symbol and sql topology which is extended into a 3D supramolecular framework by C−H⋯O hydrogen bonds interactions. Complex 2 featured a 3D network that two identical 3D self-penetrating frameworks interpenetrate each other in a 2-fold (3D+3D →3D) mode, with a pcu; 6/4/c1; sqc1 topology with the point symbol of {412.63}. The optical band gap energy values calculated by the Kubelka–Munk function for 1 and 2 observed at 3.20 and 3.24 eV, respectively. Moreover, the thermal properties of the complexes were investigated in the study.

An Experimental Correlation of Degradation with Cell Reversible and Irreversible Expansion Measurement in Pouch Cells

Lithium-ion batteries are used widely in portable devices and play an increasingly significant role in transportation and grid storage. These batteries degrade when they undergo charging and discharging and also when they are stored (calendar aging). The rate of this degradation depends on how the batteries are used and under what conditions. As the battery is cycled, its internal impedance and individual electrode capacities change, causing a change in its electrical performance. In addition, changes in the reversible and irreversible expansion of the cell are also observed. Of particular concern for pack design is the continued growth of irreversible battery thickness, thus affecting the stresses in the battery pack which is typically constrained to occupy a fixed volume. Understanding these dimensional changes will play an important role in accommodating this expansion over life for pack design.Due to the aforementioned dimensional changes, the stresses that the battery faces at the beginning of life are different from the stress at the end of life when battery expansion is constrained due to packaging. To understand the impact of external stress/pressure on battery aging, we have designed a specialized spring loaded fixture which allows for operating the battery under relatively constant pressure, over the entire cell life, while simultaneously measuring the cell expansion. Battery thickness changes were measured for 82 identical pouch cells fabricated at the UofM Battery Laboratory using Targray NMC 622 Single Crystal cathode powder and Superior SLC 1520-T anode powder. The cells were loaded into the fixtures with 4 different initial pressures of 5 psi (standard beginning of life pressure), 15 psi, 25 psi (expected end of life pressure) and without any applied pressure. A baseline cycling protocol was established which included a modest amount of fast charging and cells were divided into three different thermal chambers to simulate the impacts of environmental temperature (room 25C, cold 0C, and hot 45C). Finally the impact of depth of discharge was also included in the test matrix. Three cells were assigned to each test condition to account for cell to cell variability. Instrumenting all the cells with laboratory grade LVDT expansion sensors would be prohibitively expensive [1]. To overcome the issue we used low-cost Inductive Displacement Sensors which provide inexpensive and high-resolution measurements of battery expansion under various load conditions. Further details on the sensor design and implementation are given in [2].

Using Reference Electrodes to Validate Parameterization of Individual Electrode Soh in the Single Particle Model with Electrolyte

Most model parametrization techniques for reduced order physics-based Lithium-ion battery models like the single particle model rely on minimizing the error in the measured and predicted cell terminal voltage. The battery terminal voltage is the difference between the voltages of the positive and negative electrode solid phase potentials. If the individual contribution of each electrode overpotential to the terminal voltage, is not measured, there could be multiple combinations of parameters that provide similar RMSE for voltage prediction, yielding non-unique solutions and local minima. Misattributing the parameters for kinetics and diffusion in each electrode could result in increased plating or over-conservative designs at higher operating currents.Adding a reference electrode to the battery allows us to measure the individual electrode potentials experimentally. Using this extra measurement, we can parametrize the kinetic and diffusion reactions in positive and negative electrodes with better confidence [1], and validate the electrode-specific state of health parameterization, specifically the increased resistances due to SEI growth and shift in the stoichiometric window as the cell ages [2,3]. In our experiments, we used a pouch cell manufactured in the U of M Battery Lab with Targray NMC 622 Single Crystal cathode powder, Superior SLC 1520-T anode powder, and a custom fabricated Lithium Iron Phosphate (LFP) reference electrode deposited on a porous electrode layer. Further details of the reference electrode are given in [4]. The model was parametrized using discharge data at different C-rates and a modified Hybrid Pulse Power Characterization test. Finally, the RMSE for both the modeled negative and positive electrode potentials are calculated for the validation data set which uses the US06 Drive cycle.

Preparation of sintering-free non-crystalline Li2B4O7 ceramics for Li-ion battery’s binder

Li–B–O materials are used as binders for all solid-state lithium-ion batteries (LIBs). We obtained amorphous Li2B4O7 powder by heating treatment of precursor powder synthesized from Li(OAc)·2H2O, H3BO3, and DL-malic acid by solution method. Thermogravimetric differential thermal analysis results showed that crystallization of the precursor powder occurred at around 500 °C. Therefore, heating treatment was performed below 500 °C. As a result, the amorphous powder was obtained under the heating treatment conditions of 400 °C for 1 h in air. The obtained powder has softness and dense pellet was prepared by uniaxial pressure molding at RT. This material can be used for all solid-state LIBs as a new binder.

Preparation and magnetic properties of magnetically anisotropic 2:17-type SmCo alloy spherical particles

This study utilized the irregular Sm(Co0.69Fe0.22Cu0.07Zr0.02)8.1 alloy powder as the primary material, combining the solid/liquid interface de-wetting effect and abnormal grain growth method for preparing the 1:7-type SmCo spherical single crystal powder. Through aging heat treatment, the anisotropic 2:17-type SmCo alloy spherical permanent magnetic powder with size distribution of 30–130 μm was successfully obtained. The study explored the spheroidization mechanism and single crystal growth rule of Sm(Co0.69Fe0.22Cu0.07Zr0.02)8.1 alloy powder, as well as the impact of solution-aging magnetic hardening treatment on the permanent magnet properties. The optimized permanent magnetic properties of the resulting 2:17-type SmCo alloy spherical powder were coercivity Hic = 1244 kA/m, and maximum magnetic energy product (BH)max = 224.5 kJ/m3 at room temperature. The anisotropic 2:17-type SmCo alloy spherical magnetic powder prepared using this method exhibits significant potential applications in the production of bonded magnets.

Enhanced suppression of metal combustion processes using a compound expansible graphite extinguishing agent: Experimental study and mechanistic insights

In this investigation, we investigate the effectiveness of Expandable graphite (EG) and potassium bicarbonate (KHCO3) powders as fire suppressants. The research combines experimental and computational techniques to evaluate the efficacy of these media under a variety of conditions. Understanding the synergistic effect of these two components in varying proportions is the focus of our research. One EG sample and three composite EG–KHCO3 powders mixed at 1:1, 3:1, and 9:1 ratios were prepared as sample powders. Powders were subjected to high-velocity mixing and drying procedures to improve their hydrophobic properties and resistance to caking. We pay special attention to the 3:1 mixture of Expandable graphite and potassium hydroxide. Our experimental findings indicate that this particular mixture has superior fire suppression capabilities. Within just 2 s of administering the mixture, the flame temperature decreased by approximately 200 °C. To comprehend the mechanisms underlying this fire suppression, we investigated the chemical reactions taking place. Our research indicates that the rapid endothermic decomposition of KHCO3 and the formation of a protective layer by EG are the primary contributors to the efficiency observed. The powder's crystal phase composition was determined by X-ray diffraction analysis. Preliminary results indicate that the composition and properties of dried powder have a significant impact on its fire suppression capability. The study concludes, however, that additional research is required to optimize the properties of dried powder mediums for improved fire suppression. The implications of this study's findings for the future development of more effective fire suppression agents are substantial. They lay the groundwork for future research and development in this field.

Cadmium(II) coordination polymers based on 3,3′-azobis(pyridine) and some aliphatic dicarboxylates: Hydrothermal synthesis, crystal structures, thermal stabilities and photoluminescence

Three new Cd(II) coordination polymers (CPs), namely, [Cd2(µ-phsuc)2(µ-abpy)2(H2O)2]n (1), {[Cd(μ3-glu)(μ-abpy)]⋅3H2O}n (2) and {[Cd(μ-dmglu)(μ-abpy)(H2O)]⋅H2O}n (3), were synthesized by hydrothermally from 3,3′-azobis(pyridine) (abpy) using three different aliphatic dicarboxylic acids [phenyl succinic acid (phsucH2), glutaric acid (gluH2) and 3,3′-dimethyl glutaric acid (dmgluH2)]. The structures of 1–3 were characterized by elemental analysis, infrared spectroscopy (IR), single crystal X-ray and powder X-ray diffraction (PXRD) techniques. X-ray diffraction studies have revealed that 1–3 crystallize in the monoclinic system, P21/n space group (1) and C2/c space group (2, 3). 1 and 2 show 3D structure, whereas 3 exhibits an interesting 2-fold interpenetrating 2D structure. The thermal stabilities of the CPs were studied by thermal analysis (TG/DTA) techniques. In addition, the photoluminescence properties of the CPs have been investigated.