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The aim of the present study is to synthesize the Bi(Cd0.45Ti0.45Fe0.10)O₃ (BCTF45/10) nanoceramics by solid state reaction ceramic method at an ambient temperature. Therefore, a raw material in stoichiometric ratios of carbonates and oxide powder was employed to obtain a precursor of the BCTF45/10 nanoceramics. The as-prepared mixture is calcined at 1010 K for 4 h in an air atmosphere. Preliminary structural and surface morphological analyses were carried out using powder X-ray diffractometer and scanning electron microscopy technique, respectively. X-ray analysis of synthesized compound shows the formation of single-phase orthorhombic structure with an average crystallite size of 25 nm. The sintered bodies have relative density above 95%. A correlation between both dielectric parameter of the as-synthesized compounds were also discussed in a wide temperature (298–673 K) and different operated frequency range (1–750 kHz). Addition of Cd/Ti affected the ferroelectric property of the BiFeO₃ due to contribution from the leakage current.

Polycrystalline samples AlFe${}_{0.95}$Cr${}_{0.05}$O₃ synthetized by a solid state and a co-precipitation (cop) method show an orthorhombic system in space group Pc21n. It was found that the cation distribution and magnetic ordering depend toughly on the preparation conductions. The dielectric and conductivity properties of samples were studied as function of frequency and temperature. We deployed impedance spectroscopy in studying the dielectric behavior of AlFe${}_{0.95}$Cr${}_{0.05}$O₃. The significant results of this work are as follows: For both samples, permittivity and dielectric loss are very sensitive to temperature and frequency variation. The presence of additional effects and conducting species in AFCr5 ceramics leads to high dielectric permittivity. The activation energy values point towards the small range motion of oxygen at low-temperature and long range motion at high-temperature. The dielectric response, in case of AFCr5-s, was assigned to both grain and grain boundaries. However, additional entity pores also contribute to dielectric belongings of AFCr5-cop.

Single crystals of pure and various amount of L-lysine doped KDP crystals were grown from aqueous solution. The doping of L-lysine was confirmed by CHN analysis and FT-IR spectroscopy. Powder XRD was carried out to assess the single phase nature of the samples. The effect of doping on thermal stability of the crystals was carried out by TGA and the kinetic and thermodynamic parameters of dehydration were evaluated. It was found that as the amount of doping of amino acid, L-lysine, increased the thermal stability of the grown crystals decreased. However, the second-harmonic generation (SHG) efficiency of Nd:YAG laser and UV-vis spectroscopy studies indicated that as the L-lysine doping increased in KDP crystals the SHG efficiency and optical transmission percentage increased. The dielectric constant and the dielectric loss of L-lysine doped KDP crystals are lower than the pure KDP crystals. Hence L-lysine doped KDP crystals are found to be more beneficial from an application point of view as compared to pure KDP crystals. The results are discussed.

Bis-thiourea strontium chloride was synthesized and single crystals were grown by the slow solvent evaporation technique using aqueous solvent. The solubility curve was obtained and the determination of the induction period as well as the evaluation of kinetic parameters of nucleation was carried out. The powder XRD analysis suggested orthorhombic crystal structure. The FT-IR spectrum confirmed the presence of various functional groups. The thermo-gravimetry analysis was carried out and the crystals were found to be stable up to 170°C. Applying Coats and Redferm relation to the thermo-gram, the kinetic and thermodynamic parameters of dehydration were calculated. The dielectric study was carried out in the frequency range of applied field from 500 Hz to 1 MHz. The variations of dielectric constant, dielectric loss, AC resistivity and AC conductivity were studied with frequency. It was found that the dielectric constant and the dielectric loss decreased as the frequency of applied field increased, whereas the AC resistivity increased as the frequency increased.

Calcium phosphate based biomaterials play important roles in clinical applications. Calcium pyrophosphate (CPP), a kind of calcium phosphate, can be used as a bone substitution material as well as a bone graft. Because of its similarity to inorganic component of bone and teeth it can be used for surface coating of metallic dental and orthopedic implants. In the present study, calcium pyrophosphate dihydrate (CPPD) nanoparticles were synthesized using surfactant mediated approach. Crystalline nature and average crystallite size was studied using Powder XRD. The CPPD nanocrystallites were found to be triclinic from powder XRD. The TEM study indicated that CPPD nanoparticles were in the range of 13 nm to 20 nm. The presence of various bonds was confirmed by FTIR spectroscopy. The amount of water of hydration and the thermal stability was studied by thermogravimetry. The variations of various dielectric parameters with the frequency of applied field in 3.2 kHz to 32 MHz range and within a temperature range from 60°C to 120°C were studied. The formation of other phases such as β-CPP and α-CPP on heating of CPPD at 900°C and 1250°C, respectively, were studied by the Powder XRD. The results are discussed.

As ammonium dihydrogen phosphate (ADP) is a popular nonlinear optical crystal, to engineer its linear and nonlinear optical properties, the chalcogenide compound cobalt sulphide (CoS) was doped and the crystals were grown by the slow solvent evaporation method. To increase the solubility of CoS in water, its nanoparticles were synthesized by wet chemical technique using ethylene diamine as the capping agent followed by microwave irradiation. The nanoparticle sample exhibited finite solubility in water and was used to dope in ADP crystals. The powder XRD patterns showed the single phase nature of the doped crystals. The FTIR spectra confirmed the presence of various functional groups and EDAX gave the estimation of Co and S elements. The EPR spectroscopy also confirmed the presence of cobalt in the doped samples. TGA indicated slightly less thermal stability of the doped crystals compared to the pure ADP. The dielectric study was carried out at room temperature in the frequency range from 100Hz to 1MHz. Also, various linear optical parameters were evaluated for pure and doped crystals using UV–Vis spectroscopy. The second harmonic generation (SHG) efficiency of Nd:YAG laser was evaluated by the Kurtz and Parry method for the doped samples, it was found to be slightly lesser than that of the pure ADP crystals.

Ammonium penataborate (APB) crystals are well known for their nonlinear optical (NLO) properties. Attempt is made to study the changes produced by addition of chalcogenide compound sodium sulphide in APB crystals. Di-sodium sulphide (Na₂S) is soluble in water and its solubility is further increased for Na₂S nanoparticles. The Na₂S nanoparticles are synthesized by using co-precipitation method followed by microwave irradiation. The slow solvent evaporation method is used to grow pure and Na₂S added APB crystals. Pure and Na₂S added APB crystals possess orthorhombic crystal structure with the mixed phase nature for the Na₂S added APB. The presence of sodium in APB is confirmed by AAS study. In FTIR spectra the absorption peak of S–H asymmetric stretching is observed for Na₂S added APB indicating the presence of sulphur. The thermal stability of APB crystal is enhanced on doping the Na₂S in it. The dielectric study is also carried out within this frequency range. The Jonscher’s power law is applied to AC conductivity data. The impedance spectroscopy study is carried out at room temperature within 100 Hz to 1 MHz frequency range. The complex impedance and modulus plots are drawn. The complex impedance plots indicate only the grain contribution. The Kurtz and Perry powder study indicates that all the crystals are exhibiting NLO properties with varying SHG efficiency.

The development of crystal growth and measurement methods opens new possibilities for studying materials with remarkable nonlinear optical features. The development of bulk crystals is a constant concern to be beneficial for device applications. This study focuses on the development of nonlinear optical crystals of L-histidine complexes, characterization approaches, and prospective applications. The solution growth approach, a straightforward, inexpensive, and low-temperature growth technique, was adopted broadly. Recent studies show that L-histidine derivatives have potential optical, SHG, thermal, dielectric, and mechanical properties, making them an excellent choice for nonlinear optical devices. In this work, structural, spectroscopic, chemical composition, linear and nonlinear optical analyses, thermal, and dielectric characterizations of L-histidine derivatives were conducted. Most of the L-histidine complexes were found to be crystallized in orthorhombic and monoclinic crystal systems with P2₁2₁2₁ and P2₁ space groups. The crystalline perfections of the samples were analyzed by the HR-XRD method. The energy-dispersive X-ray (EDX) spectroscopic technique was applied to evaluate the chemical content of the compounds. FT-IR and FT-Raman techniques were used to recognize the molecular vibrations and functional groups of the L-histidine derivatives. The UV-visible and photoconductivity studies were done to examine the optical behaviors of the developed crystals. Most of the crystals were found to have excellent optical transparency and wide bandgaps. It has been observed that L-histidine hydro-fluoride dehydrate and L-histidine tetrafluoroborate are found to have the highest second harmonic generation (SHG) efficiencies. The dielectric analyses were utilized to study the dielectric constant and dielectric loss variations with the applied frequency. According to the thermal analyses, most of the crystals were found to have substantial thermal stabilities suitable for device applications.