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Dynamic shock wave induced switchable phase transitions between crystal and amorphous states of NiSO4·6H2O is reported.

Sulfanilic acid (SA) crystal has been very well established as an excellent material for the applications such as photonic, electro-optical and harmonic generation in non linear optics (NLO). This article is deliberated on good quality SA single crystal which has been grown by slow evaporation solution technique as it is a prominent NLO material. After the growth period of 95 days, a transparent SA single crystal has been collected with the dimension of 9 × 9 × 2 mm3. The grown crystal has been subjected to photoacoustic spectroscopy (PAS) and impedance analyses. The study of PAS has been utilized to find out thermal diffusivity and the observed result qualifies the crystal to be suitable for lasers and high temperature related applications. Impedance analysis has been implemented for the grown SA crystal for various values of temperature and it comes out with good results so that it could be a candidate for few applications in the field of microelectronic and electro-optical industries.

In this article, the authors investigate the structural, thermophysical and dielectric properties of glycine phosphate (GPI) crystals for pre- and post-shock wave loaded conditions. The supersonic shock waves were generated by a table-top shock tube with corresponding Mach number of 1.7. The applied shock wave has 1.048 MPa transient pressure and 644 K temperature, respectively. The changes observed in the structural properties for pre- and post-shock loaded sample were confirmed using a powder x-ray diffractometer. Thermophysical properties such as thermal diffusivity, thermal conductivity and thermal effusivity were elucidated by photoacoustic spectrometer. The impedance analyzer is employed to determine the electrical properties and domain stabilities of the GPI crystal in the frequency range from 1 Hz to 1 MHz at ambient temperature. From this investigation we conclude that the GPI crystal can be used for devices that work in high vibration and extreme environments.

Ammonium Dihydrogen Phosphate (ADP) and Potassium Dihydrogen Phosphate (KDP) crystals are grown by slow evaporation method at ambient temperature. The said crystals are utilized as a test specimen and subjected to one-dimensional ‘loading of shock waves’ generated by rupturing a paper diaphragm with Mach number of 1.9 using supersonic low energy table-top shock tube. Thermal diffusivity of crystal is measured using Photoacoustic spectrometer (PAS) for the normal and shock loaded crystals, thermal conductivity and thermal effusivity are computed for the given volumetric specific heat capacity of the crystals. XRD characterization studies reveals that KDP crystal has better immunity to shock wave than ADP crystal.

Nonlinear optical sodium sulfanilate dihydrate (SSD) single crystal was grown by slow evaporation solution method at ambient temperature. Unit cell parameters were elucidated with the study of single crystal X-ray diffraction. Fourier transform infrared spectroscopic analyses were performed to indentify a variety of functional groups present in the grown SSD crystal. The level of optical transmittance of the grown SSD crystal was investigated by UV–Vis–NIR spectral analysis. The lower cut off wavelength of the grown crystal was observed at 243 nm and the band gap energy is found to be 5.23 eV. The spectral study of photoluminescence was carried out for the grown crystal which shows a sharp emission peak at 485 nm resulting blue–green emission that is suitable for the optical communication applications. Mechanical strength was measured by utilizing Vickers microhardness test and the value of n is found to be 2.25 asserting that the crystal belongs to soft material category. The dielectric properties were studied as a function of frequency at various temperatures and also the grown SSD crystal has been correlated with electro-optic properties. Thermogravimetric analysis was undertaken by a thermal analyzer with the temperature starting from 30 to 800 °C and TGA/DTA results show that the crystal has good thermal stability and useful for laser applications. Etching analysis also was performed for the grown SSD single crystal proving that it has good crystalline nature with fewer defects.

Ammonium dihydrogen phosphate (ADP) crystal utilizes several applications such as Q-switching, electro-optical, and second harmonic generation in nonlinear optics. In the present article, a good-quality single crystal of ADP was grown via Sankaranarayanan–Ramasamy (SR) method for the dimension of 120 mm in length and 12 mm in diameter. The grown ADP crystal is used for diverse characterizations like FTIR spectral study, Vickers microhardness, second harmonic generation, photoluminescence, and chemical etching analysis. The photoacoustic spectroscopy analysis was used to study the thermal diffusivity of the sample. Thermal transport properties of the crystal are required for all types of heat transfer incidences and furthermore used in several applications like acousto-optical, Nd:YAG, and Nd:YLF lasers. A dielectric property was investigated for the grown crystal with dissimilar temperatures, and it was apt for electro-optical and Q-switching applications.

Semiorganic material of bis-glycine cobalt sulphate pentahydrate (BGCS) was synthesized and single crystals of BGCS were grown by slow evaporation technique at room temperature. Three dimensional crystal structure of BGCS crystal elucidated by single crystal X-ray diffraction analysis reveals that the crystal belongs to triclinic system with centrosymmetric P-1 space group. Fourier transform infrared (FT-IR) spectral analysis was carried out and the presence of various functional groups of BGCS were identified. UV–Vis–NIR spectral analysis of BGCS crystal shows that the crystal is transparent between the wavelengths 200 and 1100 nm. Vickers microhardness study of the BGCS was carried out. Dielectric constant and dielectric loss of BGCS crystal were measured in the frequency range of 50 Hz–2 MHz at room temperature. Thermogravimetric, differential thermal analysis and differential scanning calorimetric studies carried out for the BGCS single crystal revealed that the grown crystal is stable up to 214 °C. Thermodynamic parameter showed that the decomposition reaction of BGCS is non-spontaneous. Etching study was carried out on the surface of the crystal using double distilled water as etchant. Increase in the etching time from 10 to 15 s developed staircase shaped etch pattern. The thermal parameter of BGCS was calculated from photoacoustic spectroscopy. Antibacterial activity was carried out in-vitro against gram negative i.e. Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi; gram positive bacteria Staphylococcus aureus.

Lithium manganate (LM) has been extremely well established as a material for applications in electronic devices such as personal organizers, pagers, personal computers, facsimile machines, portable stereophonic equipment, and cellular phones. LM nanoparticles have been prepared via the sol-gel method through a stoichiometric quantity of Manganese acetate tetrahydrate, Lithium hydroxide monohydrate, and Citric acid anhydrous taken in 1:2:3 ratios. The calcination was done with the resulting powder samples at different temperatures of 600°C and 700°C. The LM powder samples were utilized for dissimilar characterizations for FTIR spectral analysis exhibiting the presence of functional groups. PXRD result illustrates that the "h, k, l" values are well matched by the earlier reported values. The dielectric properties are calculated at different temperatures from 50°C to 350°C. When the calcination temperature increases the conductivity of the sample also increases. The dielectric loss and dielectric constant confirm the normal dielectric behavior of the material. XPS results show the measured empirical formula, elemental composition, and electronic state of the elements in a material. Photoacoustic spectroscopy analysis of the title compound values makes it a promising material for Li-ion battery and electrical storage devices applications.

Organic nonlinear optical benzil single crystal of fine quality with the dimensions of 168 × 14 mm2 was successfully grown in (100) plane from saturated solution by unidirectional SR method. The structural identity of the grown crystal was confirmed by powder XRD. High-resolution X-ray diffraction analysis indicates the crystalline perfection of the grown benzil crystal. The optical analysis was carried out by UV–visible spectroscopy which shows that the benzil crystal’s cut off wavelength is 437 nm. The dielectric constant and dielectric loss of benzil crystal are found to be very much depending upon temperature and frequency. Ferroelectric nature of grown crystal was identified by P–E hysteresis analysis and to find the values of spontaneous polarization and coercive field. The laser damage threshold energy was studied with the help of Nd:YAG laser. The presence of third harmonic generation was identified by z-scan techniques.