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The high-pressure structural phase transition and pressure induced elastic properties of cubic zinc-blende phase (B3) to rock-salt phase (B1) structure of Zinc Telluride (ZnTe) semiconducting compound were studied by using the effective inter-ionic potential method, which contains the long-range Coulomb and van der Waals (vdW) interactions and the short-range repulsive interaction of up to second-neighbor ions within the Hafemeister and Flygare approach. The structural phase transition from B3 to B1 structure is reflected using estimated values of phase transition pressure and volumetric abrupt changes in the pressure–volume phase diagram. The calculated results first predict the phase transformation of ZnTe from B3 to B1, which occurs at 19GPa and is consistent with the reported data. Later on, using the effective inter-ionic potential technique, we were able to predict the second order elastic characteristics of the ZnTe system.

In the present work, a polyphenylene oxide/Polyvinyl pyrrolidone (PPO/PVP) thin film has been synthesized by using a spin coating technique. The structural and optical properties of the thin film were studied by using X-ray diffraction and optical absorption spectroscopic techniques. The XRD results showed that precursor polymers PPO and PVP along with PPO/PVP-based polymer film exhibited amorphous behavior. Optical properties were obtained using UV–Vis spectroscopy. Two absorption peaks were identified in the UV area, at 311 nm and 367 nm, respectively, and the optical band gap of the PPO/PVP film was found at 2.9 eV. The synthesized PPO/PVP thin film had an Urbach energy of 0.294 eV, as per the findings.

Zinc oxide nanoparticles have recently become a popular study topic because of their intriguing physical and chemical properties and their potential applications in optoelectronics, chemical sensing, bio-sensing, and photo-catalysis. Present study reports a new, template and solvent less solid-state synthesis of ZnO nanoparticles. The synthesis route includes the thermal degradation of novel starting reagents i.e., zinc acetate dehydrate and ethylene glycol at 500 °C for 3 h. XRD was used to determine crystalline structure, EDXS was used to determine chemical composition, FESEM was used to evaluate size and morphology and to determine the optical characteristics of the as-prepared product, UV–Visible spectroscopy was used. These results showed that ethylene glycol inhibits nanoparticles from sintering and leads to the creation of homogenous particles with an optical band-gap of 3.39 eV with an average particle size of 35.4 nm.

This work presents the influence of La3+ and Sr2+ substitution at Bi-site of BiFeO3 in the sense of phase, crystal structure and dielectric properties. The Bi1-x (Lax-y Sry)FeO3 (x = 0.1, y = 0, 0.05) ceramics with perovskite structure were synthesized by standard solid state route. Phase analysis exploiting X–ray diffraction (XRD) data disclosed formation of single phased trigonal structure with R3c space group. The calculated lattice parameters for Bi0.9La0.1FeO3 ceramic were a = b = 5.5771 A and c = 13.8021 A and Bi0.9La0.05Sr0.05FeO3 ceramic were a = b = 5.5844 A and c = 13.8215 A which witness trigonal structure. The calculated average crystallite size for Bi0.9La0.1FeO3 and Bi0.9La0.05Sr0.05FeO3 ceramics were 47.39 nm and 31.20 nm respectively. The dielectric analysis reveals that both the ceramics to exhibit good dielectric behavior with high dielectric constant and lower tangential loss value. In addition, Cole-Cole plot (M′ vs. M′′) and Nyquist plot (Z′ vs Z′′) exposed the non-Debye behavior of the ceramics and distribution of different relaxation phenomena in the ceramics.

In this work, we discuss the synthesis, characterization and dielectric properties of Bi[Formula: see text]La[Formula: see text](Ba/Sr)[Formula: see text]FeO3 [[Formula: see text]] ceramic compounds. These samples were synthesized via a solid-state reaction method and then characterized for structural analysis exploiting the X-ray diffraction (XRD) technique. The Rietveld refinement data inferred that all the prepared samples were acquired a monoclinic phase with space group C1c1. Field emission scanning electron micrographs (FE-SEM) images of the samples indicated highly grown grains with a moderate level of grain boundary development across the sample. The energy dispersive analysis of the X-ray (EDAX) diffraction spectra analysis confirmed that the composition was free from foreign impurities. Further, UV–Vis experiment was conducted and estimated average value of optical bandgap was about 2.2 eV, which is highly recommended for photocatalytic and opto-electronic device applications. Room-temperature dielectric studies revealed that samples were extremely good dielectric materials with low dielectric loss, which is important for storage device applications. In addition, the depressed semicircles obtained from impedance analysis indicated that the samples exhibited distributed relaxation times and non-Debye behavior.

This report throws light on the synthesis and characterization of the Cu-Zn ferrites of the type Cu0.5-xBaxZn0.5Fe2O4 [x = 0, 0.05, 0.1]. The solid state reactions route was used for synthesis of ferrites under consideration. To confirm the structure, phase and lattice formation, these materials were characterized by X-Ray diffraction and Raman spectroscopic techniques. In addition to the structural study, the samples were investigated for dielectric. The XRD data analysis conferred that all the prepared samples have acquired cubic structure and exhibit Fd3m space group. The diffractograms are same in appearance with no new reflection visible in the limits of experimentation revealing the sample to be mono-phase in nature. With the display of signature vibration modes by all the samples, the lattice structure formation was confirmed. The dielectric studies showed the ferrites under study to be exhibiting low dielectric constant with low decreasing rate with increase in the applied field. Furthermore, the samples have low loss values which increase their ability for advanced technological applications.

Transport properties such as thermal conductivity (κ), Seebeck coefficient (S) and electrical resistivity (ρ) of the FeSe superconductor were measured and analyzed theoretically. The samples were synthesized through a solid-state reaction route via vacuum encapsulation and characterized by X-ray diffraction and Rietveld refinement analysis. It is found that the Seebeck coefficient, S(T), exhibits an anomalous temperature dependence and shows a crossover of sign at around 190 K, which is an artifact of coexistence of electron and hole bands, wherein carrier diffusive Seebeck coefficient Sdiff(T) and phonon drag contribution Sdrag(T) can successfully explain the experimental results. The measured thermal conductivity κ(T) develops a phonon peak at around 80 K, presumably due to various phonon scattering mechanisms. Our thermal conductivity analysis indicates not only phonon thermal conductivity (κph), but also the carrier contribution to thermal conductivity (κc) is also important, particularly, around room temperatures. Electrical resistivity of FeSe shows superconducting transition (TC) around 10 K and shows a metallic temperature dependence above TC which is explained using the Bloch–Gruneisen function of the temperature-dependent resistivity.

Cr doped nickel oxide (NiO) were successfully synthesized using a one-step solid state reaction method. The X-ray diffraction patterns analysis shown that all doped NiO powder samples were exhibited polycrystalline structures. When NiO doped with the different elements such as Cr then substantial modifications and anomalies were observed in NiO such as, morphology, thickness, lattice constant, stress/strain, crystallite size, and dislocation density. The doping in NiO also altered optical properties. Moreover, the characteristic deviations in the doped NiO powder have been thoroughly discussed.

The composites of the form 0.5ZFO + 0.4BFO + 0.1GFO (S1) and 0.75ZFO + 0.2BFO + 0.05GFO (S2) and synthesized by solid state route are reported in this study. These composites were subjected to structural, energy bandgap and dielectric studies. The XRD spectral analysis confirms that all the three phases are present in the samples under study. The BiFeO3 phase has acquired orthorhombic (Pnma) crystal structure, ZnFe2O4 has crystallized into cubic (Fd-3m) structure where GaFeO3 exhibited trigonal (R3c) structure. Diffuse reflectance spectral study conveys the sample to possess wide energy bandgap ≈2eV. The dielectric studies reveals the samples are extremely good dielectric materials with average dielectric constant, low loss value and relatively low decreasing rate with respect to applied field for both features.

Through dip coating method monodisperse nickel nanoparticles assisted carbon membrane was prepared on porous alumina disc support. The coating solution was prepared by blending of thermally stable polymer polyphenylene oxide (PPO) and thermally labile polymer polyvinylpyrrolidone (PVP) followed by addition of nickel nanoparticles. Size of nanoparticles, surface porosity, average pore size, element composition and optical properties of the membrane were investigated by means of different techniques such as XRD, FE-SEM, EDS and UV-Visible spectrometer Incorporation of nano-sized nickel in polymer matrix causes increase in pore size from 0.022 µm to 0.076 µm as well as porosity and decrease in optical band gap from 5.44 eV to 5.09 eV of membrane.

The structural properties strontium oxide (SrO) in two phases, namely, Rocksalt (B1) and Cesium Chloride (B2) phases, and a structural transition from B1 to B2 structures are presented. We have estimated the effect of pressure on structural and elastic properties of SrO semiconducting material using an effective inter-ionic potential method, which contain the long-range Coulomb and van der Waals (vdW) interactions and the short-range repulsive interaction of up to second- neighbor ions within the Hafemeister and Flygare approach. To calculate the vdW coefficients Slater-Kirkwood variational method was used. Our calculated phase transition pressure (Pt) is 38.5 GPa. We have also focused on the elastic properties of SrO compound within the effective inter-ionic potential approach and the second order elastic constants (SOEC) were predicted in both the phases. The present calculations have provided a good agreement with the available data reported on this compound.

In this article, we studied theBi0.9La0.1FeO3 (BLFO) and BaTiO3 (BTO) and their composite (0.85) Bi0.9La0.1FeO3-(0.15) BaTiO3 for their structural and dielectric properties. The samples were prepared via conventional solid state reaction route. The X-ray diffraction spectroscopy analysis reveals the rhombohedral crystal structure for BLFO and Cubic structure for BTO. While, Bi0.9La0.1FeO3−(0.15) BaTiO3 depicts the presence of both the phases. The compositional and morphological studyof the composite was also carried out. The frequency dependent dielectric analysis shows that the samples exhibit a good dielectric property with low loss in directric values. The ac conductivity at lower frequency shows independent of the field but after the threshold value of frequency, the conductivity increases due to hopping of charge carriers. It is concluded that the samples are promising candidates for good energy storage capability, required in storage device applications.

The present paper address the pressure-induced phase transitions from the sixfold-coordinated NaCl structure (B1) to the eightfold-coordinated CsCl structure (B2) in IIA–VI chalcogenide compounds, and their ternary mixed crystals BaSe1-xSx for 0 ≤ x ≤ 1 by applying an effective interionic interaction potential, which includes the long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach. Assuming that both the ions are polarizable, the Slater-Kirkwood variational method is employed to estimate the vdW coefficients for parent compounds. The estimated values of the phase transition pressure (Pt) increase with S concentration. The vast volume discontinuity in pressure volume phase diagram identifies the structural phase transition from B1 to B2 structure.

Herein, we throw light on the structural, optical and microstructural properties of 0.9ZFO + 0.1 GFO and 0.78ZFO + 0.22GFO composites materials. The materials were investigated for the crystal structure and desired composite formation using X-ray diffraction technique. For microstructural studies and compositional investigation, we employed reliable Field Emission Scanning Electron Microscopic (FESEM) and energy dispersive analysis of X-ray (EDAX) techniques respectively. For Optical bandgap determination, we exploited UV-Vis spectral analysis as a tool. From XRD diffractogram, diffraction peaks corresponding to both the ZFO and GFO phase were witnessed. It was found that ZFO has acquired cubic structure and GFO has crystallized in trigonal phase. FESEM micrographs reveals higher grain size with no defined grain boundaries i.e. samples exhibit porous nature. EDAX spectra infers the constituents of the composite are present with absence of any trace of impurity. The bandgap was found to be 3.4 eV for 0.9ZFO + 0.1 GFO and 3.2eV for 0.78ZFO + 0.22GFO composite.

Transition metal oxides of the type Mo1-xFexO3 (x = 0.01, 0.02, 0.05) are reported in this work. These metal oxides were synthesized by the solid state reaction method. The as synthesized metal oxides were studied for structural properties using X-ray diffraction characterization. The data collected in the angular range of 20° ≤ θ ≤ 60° was analyzed and it was found that all the synthesized oxides have acquired orthorhombic (Pbnm) crystal structure. It was witnessed that all sample were single phased inferred from the identical diffractogram of these oxides. To verify the results of XRD analysis further, we refined the XRD data and the various structural parameters obtained established the structure and space group of the prepared oxide materials. To obtain the crystallite size acquired as a result of high temperature firing, we approached with classical Debye-Scherer formula and Williamson-Hall approach and the calculated crystallite size in both approaches agree with each other. Further, Williamson-Hall approach helped us in the determination of the strain induced as a result of severe mechanical grinding and high temperature treatment. The optical bandgap estimated exploiting UV-Vis spectroscopic technique was found 3.34eV, 3.5eVand 3.3eV for Mo0.99Fe0.01O3, Mo0.98Fe0.02O3 and Mo0.95Fe0.05O3 oxides respectively.

The composite of the formula (0.75) Cu0.5Zn0.5Fe2O4 + (0.25) BaZr0.5Ti0.5O3 has been discussed in this report. The structural studies were carried out using via X-ray diffraction technique and temperature dependent dielectric properties were examined at a constant field value of 500Hz. The X-ray diffraction data analysis reveal the presence of both the constituent phases. The ferrite Cu0.5Zn0.5Fe2O4 phase has attained cubic structure having space group Fd-3m and BaZr0.5Ti0.5O3 has acquired hexagonal crystal structure with space group P 63/m m c. The morphological and compositional studies were carried out. The as synthesized composite sample was studied for dielectric nature as a function of temperature (120K-320K) at a field of 500Hz. The dielectric constant was observed to initially increasing slowly but as the temperature enhances, dielectric constant increases rapidly near room temperature. Dielectric loss follows same trend with two humps corresponding to the two phases of the composite. The ac conductivity was observed low in the low temperature range and become higher in the extended temperature values.

In this presented work, we report the synthesis and characterization of A-site doped multiferroic BiFeO3 by La3+ and Ba2+ The perovskite Bi1-x (Lax-y Bay)FeO3 (x = 0.1, y = 0, 0.05) samples were synthesized using high temperature solid state reaction route and were characterized for structural studies using X-ray diffraction and Raman spectral studies. The Bi(La/Ba)FeO3 samples were further studied for frequency dependent dielectric properties at room temperature. The XRD spectrum analysis infers the samples to be crystalline in nature as well as single phased. The XRD spectral study of as synthesized samples further reveals their crystallization into the trigonal structure with an assigned space group R3c. The intense reflection peaks witness the crystallinity and narrow fullwidth at half maximum indicate the higher average particle size. The average particle size calculated using Scherrer’s formula was 47.39nm for La and 34.32 nm for La/Ba doped BiFeO3. The lattice parameters calculated for La doped BiFeO3 were a = b = 5.5771A and c = 13.8021A and La/Ba doped BiFeO3 were a = b = 5.5844 A and c = 13.8215 A which witness acquired trigonal structure. The dielectric studies reveal the Bi1-x (Lax-y Bay)FeO3 (x = 0.1, y = 0, 0.05) samples to be good dielectric in nature with lower dielectric loss values. The ac conductivity study reveals the samples to be resistive to the applied field to a higher value thereby does not respond but after the certain limit of the applied field, the conductivity abruptly increases which is attributed to the release of the charge carriers by the trap centers after a threshold voltage. The intriguing dielectric and loss character infer these samples is feasible for electo-magnetic device application.

This chapter gives a general overview of synthesis and recent development of nickel oxide as a nonstoichiometric compound. We establish the synthesis chemistry of nickel oxide as a nonstoichiometric material, and hence successively introduce definitions and classifications of nonstoichiometric compounds as well as their point defects. The samples of nonstoichiometric nickel oxide are synthesized by thermal decomposition method. The nonstoichiometry of samples was then studied chemically by iodometric titration, and the results are further corroborated by excess oxygen obtained from the thermo-gravimetric analysis (TGA). X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) techniques are used to analyze structural phase of nonstoichiometric nickel oxide. The change in oxidation state of nickel was studied by X-ray photoelectron spectroscopy (XPS) analysis. The shift in antiferromagnetic ordering and transition temperature due to nonstoichiometry is studied by magnetic and specific heat capacity analysis.

In this study, we determined the structural, electrical, and thermal transport properties of the FeTe 1− x S x system, where x = 0.0, 0.1, 0.2, and 0.3. The samples were synthesized using a standard solid-state reaction route via vacuum encapsulation and characterized by X-ray diffraction, which indicated a tetragonal phase with the P4/nmm space group. The parent compound FeTe exhibited an anomaly according to the resistivity measurements at around 67 K due to structural change. The S-substituted samples exhibited negative dependence on the temperature at an electrical resistivity above 10 K, and quantitative analysis indicated that the variable range hopping mechanism governs electrical conduction in the FeTe 1− x S x system. In the low-temperature regime, the Seebeck coefficient, S ( T ), had an anomalous dip feature with crossover of the sign, which can be understood based on the phonon drag contributions and the multiband picture, respectively. The lattice phonons made major contributions to the measured thermal conductivity, κ ( T ). In addition, we observed a reduction in the height of the low-temperature phonon peak with κ due to the substitution of S for Te, thereby indicating strong enhancement of the disorder-induced phonon scattering. Moreover, a positive d κ /d T was observed in the normal state, which might be related to local anharmonic lattice distortions. Overall, based on our analyses, we conclude that phonons play important roles in the transport properties of FeTe 1- x S x superconductors.

We have measured Seebeck coefficient (S) of FeTe0.5Se0.5 superconducting sample from 10 to 300 K. The variation of Seebeck coefficient with temperature of this system was found to be very anomalous, and the overall experimental observation of the S(T) was studied in the outline of a narrow-band model. In high-temperature region, the Seebeck coefficient is almost independent of temperature. Further, from the study of high-temperature magnitude of S, sample undergoes a change in sign in the Seebeck coefficient, wherein, appearance of a negative peak around 22 K and subsequently, its Seebeck coefficient goes to zero in the superconducting transition temperature regime around 11 to 13 K. It is revealed that the bandwidth and a small asymmetry involved in narrow bands give a realistic explanation to the anomalous temperature dependence of Seebeck coefficient of FeTe0.5Se0.5 system.

Hereby, we report the synthesis of composites (1-x) Cu0.5Zn0.5Fe2O4 + (x) BaTiO3 [x = 0.075, 0.225] by the solid state method. The samples are prepared by the three step process where the constituent phases are individually synthesized and mixed in the stoichiometric ratio to obtain the final product. Although, the samples are intended to magnetodielectric and magnetoelectric effect studies, we report the analysis on structural and electrical properties in this work. The constituent samples of the composite were single phased cubic structured with space group Fd-3m for CZFO and Pm-3m for BTO phase. The XRD data analysis revealed the mixed diffractogram that exhibits both the phases. The dielectric property studies revealed the higher BTO phase containing composite to be highly dielectric compared to the low concentrated composite. The loss value of highly doped BTO is high and vice versa and both the samples show relaxation phenomena. Cole-Cole plot study revealed the current composite ferrite samples exhibit non-Debye character and thereby inherit spread of relaxation time.

We have carried out structural and elastic propertiesof Gallium Phosphide (GaP) semiconducting compound. For this Purpose, we used effective inter-ionic potential method, which consist of the long-range Coulomb and van der Waals (vdW) interactions and the short-range repulsive interaction of up to second-neighbor ions within the Hafemeister and Flygare approach. First, we used the Slater-Kirkwood variational method to estimate the vdW coefficients. The estimated value of the phase transition pressure (Pt) is 26GPa for B3(ZnS) type phase structure to B1(NaCl) type phase structure, which is agreeing with the experimental and theoretical reported data. We have also predicted the elastic properties of GaP compound within the effective inter-ionic potential approach.

This study comprises of study on the synthesis and characterization of the Cu-Zn ferrites of the type Cu0.5Zn0.5-xBaxFe2O4 [x = 0.05, 0.1]. We used solid state (ceramic) reaction route to synthesize these ferrite samples. All the prepared materials were subjected to X-Ray diffraction and Raman spectral characterization techniques to confirm the structure, phase and lattice formation. The analysis of XRD data conveyed that all the prepared samples have acquired cubic structure and exhibit Fd3m space group. The diffractograms are same in appearance and there is no new reflection visible within the limits of experimentation. This reveals the sample are mono-phase in nature where host site is effectively occupied by the dopants. The lattice structure formation was witnessed via Raman spectral analysis with signature modes displayed by all the samples. These ferrites were investigated for optical bandgap studies and the values were found to be 1.38eV, 1.43eV and 1.44eV for pristine, 5% and 10% Ba2+ doping concentrations respectively.

Temperature-dependent transport properties of a FeTe parent compound have been investigated by measurements of electrical resistivity $$\rho (T)$$, thermal conductivity $$\kappa (T)$$ and Seebeck coefficient S(T). The sample was synthesized using a standard solid state reaction route via vacuum encapsulation and characterized by X-ray diffraction spectroscopy, which indicated a tetragonal phase with the space group $$P4/{ nmm}$$. The resistivity measurement data of the parent FeTe compound do not exhibit superconductivity however, it shows an anomaly in the temperature-dependent resistivity at around 67 K, which corresponds to structural phase transition in the vicinity of a magnetic phase transition. In the low temperature regime, Seebeck coefficient, S(T), exhibited an anomalous dip feature and negative throughout the temperature range, indicating an electron-like, single band charge carrier mechanism. We have also estimated the power factor and thermoelectric figure of merit ZT, which is found to be significantly smaller than other compositions of iron chalcogenides.

We report a phenomenological model based calculation of pressure-induced structural phase transition and elastic properties of ZrN compound. Gibb’s free energy is obtained as a function of pressure by applying an effective interionic interaction potential, which includes the long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach. From the present study, we predict a structural phase transition from NaCl structure (B1) to the CsCl structure (B2). The variations of elastic constants with pressure follow a systematic trend identical to that observed in others compounds of NaCl type structure family.

The perovskite manganites compounds with nominal composition YMn 1-x Ru x O 3 (YMRO) ( x = 0, 0.05, 0.1 and 0.2) were investigated systematically through structural, morphology and thermal transport measurements. Our thermopower and specific heat measurements indicate that the ground state of rare earth manganite compounds is highly sensitive to the ruthenium (Ru) concentration at Mn-site and henceforth to its cationic radius. These properties were analyzed by considering various models and empirical relations. The high value and complicated temperature dependence of thermopower (S) is an indication of electron–magnon scattering in these systems. The observation of giant suppression in the S with increasing Ruthenium content confirms the mixed-valence subsistence of Mn - Ru network. Specific heat measurements depict an anomaly in the vicinity of T N and associated entropy change, was then obtained by subtracting the lattice part from the experimental data, indicating the existence of magnetic ordering and magnetic inhomogeneity in the samples.

A theoretical study of the elastic behavior in IrN compound using effective interionic interaction potential is carried out. The estimated values of phase transition pressure and the vast volume discontinuity in pressure-volume (PV) phase diagram indicate the structural phase transition from zinc blende (B3) to CsCl structure (B2). C11, C12 and C44 increase nearly linearly with pressure. At phase transition pressure IrN has shown a discontinuity in second order elastic constants, which is in accordance with the first-order character of the phase transition.

The high-pressure technique is useful to understand physical properties because the technique can directly control bond length and phase transition. As a general trend, the pressure-induced phase transition causes an increase of coordination number with a drastic change of their physical properties. Here, we attempt to explore the pressure-induced phase transitions from the sixfold-coordinated NaCl structure (B1) to the eightfold-coordinated CsCl structure (B2) in MgxCd1−xO by applying an effective interionic interaction potential, which includes the long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach. Assuming that both the ions are polarizable, the Slater-Kirkwood variational method is employed to estimate the vdW coefficients for parent compounds. The estimated values of the phase transition pressure (Pt) increase with Mg concentration. The vast volume discontinuity in pressure volume phase diagram identifies the structural phase transition from B1 to B2 structure. The results obtain from the present calculations requires the complete understanding of many physical interactions that are essential to ternary oxides, containing elements with size and chemical mismatch, will lead to a consistent explanation of the documented structural properties.

Non-stoichiometric nickel oxide was synthesized by solid state route method at different sintering temperatures upto 1100 °C. The structure of synthesized compounds were analyzed by X ray diffraction analysis (XRD) and the dielectric constant was found to different for samples of different stoichiometry. These results were interpreted as the decomposition temperature increases, which heals the defects present in the non-stoichiometric nickel oxide and loss peak shifts to the higher frequency which is due to long range hopping of charge carriers.

Zn doped NiO samples have been synthesized by solid state reaction method, using Nickel oxide and Zinc Oxide as a precursors, at 1000 °C. The structure of synthesized compounds was analyzed by X ray diffraction analysis (XRD) and FTIR spectroscopy studies were employed to understand the influence of doping Zn on the structural and spectroscopic properties of the NiO compound. The results revealed that Zn doping has significant influence on crystallinity and particle size of the nickel oxide. The NiO bands were also shifted towards lower frequency region because of Zn doping.

In the present investigation, we have prepared FeTe and FeTe0.9S0.1 compounds via conventional solid-state reaction method. We have measured X-ray diffraction and Raman spectra of poly-crystalline FeTe and FeTe0.9S0.1 at room temperature. X-ray profile of FeTe and FeTe0.9S0.1 confirmed the primitive tetragonal unit cell. Further, Raman active mode corresponds to A1g (Te) Te vibrations are at around (395 cm-1) B1g ((Fe)), corresponds to Fe vibrations (598 cm-1) and the E2g (Te, Fe)) modes were found to doubly degenerated at (473 cm-1). The mode observed in the spectrum of Raman at 1301 cm-1 is extremely near to the energy difference between x2-y2 and xz/yz which attributed to electronic Raman scattering in d-orbitals of Fe.

Among multifunctional La2BB’O6 (B/B’ are transition metals) with d6-d0 nature, double perovskites, La2NiTiO6 has recently received significant attention due to its rich physics and prospects in technological applications. In the present study, La2NiTiO6 (LNTO) was synthesized via citrate route. The profile analysis of room temperature X-ray diffraction data emphasized on the formation of single phase monoclinic (P21/n) LNTO ceramics. While, in order to optimize the type of band-to-band transition in the synthesized sample, the optical absorbance spectra recorded in the wave length range (200-1100) nm.

Structural and elastic properties of WN has been investigated using theoretical model calculations. The long range Coulomb, van der Waals (vdW) interaction and the short range repulsive interaction up to second-neighbor ions within the Hafemeister and Flygare approach with modified ionic charge are properly incorporated in effective interionic potential (EIOP) model. We first deduced vdW coefficients with the help of Slater-Kirkwood variational method. A structural phase transition from ambient ZnS (B3)-type structure to NaCl (B1)-type was identified in pressure volume curve in WN compound. The estimated value of transition pressure is 2GPa in WN compound. Further, the variation of second order elastic constants (C11, C12 and C44) were followed the systematic decreasing trends with pressure.Structural and elastic properties of WN has been investigated using theoretical model calculations. The long range Coulomb, van der Waals (vdW) interaction and the short range repulsive interaction up to second-neighbor ions within the Hafemeister and Flygare approach with modified ionic charge are properly incorporated in effective interionic potential (EIOP) model. We first deduced vdW coefficients with the help of Slater-Kirkwood variational method. A structural phase transition from ambient ZnS (B3)-type structure to NaCl (B1)-type was identified in pressure volume curve in WN compound. The estimated value of transition pressure is 2GPa in WN compound. Further, the variation of second order elastic constants (C11, C12 and C44) were followed the systematic decreasing trends with pressure.

Among multifunctional La2BB’O6 (B/B’ are transition metals) double perovskites, La2NiTiO6 has recently received significant attention due to its rich physics and prospects in technological applications. In the present study, bulk La2NiTiO6 double pervoskite sample has been synthesized using sol-gel method. Rietveld profile analysis of the low temperature X-ray powder diffraction data of the sample at the room temperature have emphasized on the formation of single phase monoclinic (P21/n space group) La2NiTiO6 compound. The lattice parameter and atomic positions have computed with the help of different crystallographic software’s using FULLPROF & Vesta structure simulation program, and compare these data with SPuDS structure prediction simulation software’s data.