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Hexamethylenetetramine succinate was synthesized and good quality single crystals with the size of 14 mm × 6 mm × 4 mm were grown by the slow evaporation solution growth technique at room temperature. The single crystal XRD revealed that the grown crystal belongs to the monoclinic system with the space group of P2₁/c. The presence of functional groups in the crystal was identified using FT-IR technique. The optical behavior was examined through UV-Vis-NIR studies. The photoconductivity study exhibited the positive photoconductivity nature of the grown crystal. Microhardness studies revealed the soft nature of the crystal. The nonlinear refractive index (n₂), nonlinear absorption coefficient (β) and third order nonlinear optical susceptibility χ⁽³⁾ of the crystals were measured by Z-scan studies.

Optically transparent single crystals of 2-amino 4-methylpyridinium salicylate were successfully grown by slow evaporation solution growth technique at room temperature. The grown crystal was characterized by various characterization techniques such as single crystal X-ray diffraction, Fourier transform infrared microscopy, optical, dielectric and Z-scan studies. The presence of various functional groups was identified by Fourier transform infrared technique. UV-Vis-NIR studies implied the absence of absorption in the visible region. Dielectric studies were carried out in the frequency range from 50 Hz to 5 MHz. Thermogravimetric/differential thermal analysis and nuclear magnetic resonance spectra studies were also performed for the grown crystal. Nonlinear refractive index, absorption coefficient and third order nonlinear optical susceptibility of the crystals were evaluated by Z-scan studies.

In the present work, with an aim of developing new useful materials, carbon dot-graphene oxide-zinc oxide (CGZ) nanocomplexes were synthesized by the wet chemical method. Structure, morphology and chemical composition of prepared GCZ nanoparticles were determined by carrying out X-ray diffraction, scanning electron microscopy, Fourier transform infrared and energy dispersive X-ray absorption spectral measurements. The strong absorption band observed in the UV region for the prepared samples can be attributed to the band edge absorption. The dielectric parameters, viz. dielectric constant (∈_r), dielectric loss (tanδ) and AC electrical conductivity (σ _AC) were determined at various temperatures in the range of 30 °C to 150 °C at two different frequencies (100 Hz and 1 kHz). DC conductivity (σ_DC) measurement was also carried out at various temperatures in the range of 30 °C to 150 °C. In addition, the enhanced photocatalytic activity of CGZ has been explained and the mechanism elucidating the excellent performance of CGZ has been proposed.

Single crystals of ammonium oxalate monohydrate (AO) were grown using the slow evaporation solution growth technique. The cell parameters obtained from the single crystal diffraction experiments matched with those known earlier showed that the grown crystals were composed of AO. The variation of dielectric constant as a function of frequency shows that the dielectric constant is relatively high in low frequency region and low in the high frequency region. Microhardness study indicates that the grown AO crystal is of a soft nature. The TG and DTA studies reveal that the grown crystal has good thermal stability and can be exploited in various applications up to 100 °C. There is a change in morphology of etch pits on prolonged etching. A very low value of dielectric constant supports that the material can be exploited in photonic and electro-optic devices. Thermal stability of the grown crystal is good.

The purpose of this work is the study of the correlation between the thickness of tantalum pentoxide thin films and their three-dimensional (3D) micromorphology. The samples were prepared on silicon substrates by electron beam evaporation. The differences in surface structure of the processed and reference samples were investigated. Compositional studies were performed by energy-dispersive X-ray spectroscopy. Stereometric analysis was carried out on the basis of atomic force microscopy (AFM) data, for tantalum pentoxide samples with 20 nm, 40 nm, 60 nm, 80 nm and 100 nm thicknesses. These methods are frequently used in describing experimental data of surface nanomorphology of Ta₂O₅. The results can be used to validate theoretical models for prediction or correlation of nanotexture surface parameters.