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The present study focusses on the shielding parameters (X-ray and gamma radiation) such as mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), Tenth Value Layer (TVL), Half Value Layer (HVL), electron density, effective atomic number, specific gamma ray constant and radiation protection efficiency in some iron boron alloys such as Fe0.95B0.05 (A), Fe0.9B0.1 (B), Fe0.8B0.2 (C), Fe0.7B0.3 (D), Fe0.6B0.4 (E) and Fe0.5B0.5 (F). We also investigated the neutron shielding properties (NSP) such as coherent and incoherent neutron scattering length and cross section. Then the total neutron scattering and absorption cross sections were evaluated along with the radiation protection efficiency in the iron boron alloys. The shielding properties of the various iron boron alloys were compared. It is clear from the detailed study that the iron boron alloy Fe0.95B0.05 is a perfect absorber for x-ray, gamma and neutron radiation. We therefore suggest that the iron boron alloy Fe0.95B0.05 is a good shielding material for gamma, neutrons and x-rays.

Objectives: To calculate the optical and structural parameters of the copper sodium tartrate (CuNaT) crystal for investigating its usefulness in the non-linear optics, it was analyzed by XRD and optical studies. Methods : A good nonlinear optical CuNaT crystal was grown by silica gel medium. The fundamental factors to prepare the silica gel for the controlled and defect - free growth of the CuNaT crystal are gel pH, gel density and gel setting period. Findings:The non-centro symmetric structure with refined lattice parameters: a = 7.7230 A, b = 20.2964 A, c = 7.9896 A and the required functional groups: O-H, M-O,C-O and C=O bonds of CuNaT were recognized by the XRD and FTIR studies. Novelty: The monoclinic structure and space group P21 of grown CuNaT crystal was non-identical to the orthorhombic structure of the copper tartrate crystal was enabled to identify its novel structure. The NLO competence of the CuNaT was 0.38 times relative to KDP and of higher LDT value than the KDP, provided its novel optical properties. Applications: The strong intensity emission peaks recorded at 297 nm and 380 nm in the photoluminescence spectrum and the lower absorption edge at 334 nm in the UV spectrum of the CuNaT crystal exhibited its potential use in non-linear optics. Keywords: Single crystal XRD; FTIR; UVVisNIR; PL; SHG; LDT

A new copper (II) sodium (I) tartrate trihydrate with general formula of [(Na2 Cu2 (C4H4O6) 3 (H2O) 3) 3H2O] (NaCuT) was synthesized and grown from the silica gel. The monoclinic structure and the space group P21 of the as-grown crystal are calculated and non identical with copper tartrate is found by the single crystal and powder X-ray diffraction studies. The presence of O H, C O, C O, C H and M O bonds were confirmed by Raman FTIR spectroscopy. The UV spectrum showed the transmittance in the Ultra-Violet region about the lower cutoff wavelength at 310.5 nm which makes the material to be suitable for UV filters. Different decomposition stages with respect to the mass loss of the copper sodium tartrate were studied by thermo gravimetric analysis. Occurrence of the improved electrical conductivity by the pi electrons of the C O and O-H----O groups of the CuNaT crystal was established by the dielectric studies. From Z-scan studies, the present sample proved its suitability for non linear optical applications.

A new organic optical limiting material, ethylenediaminium picrate (EDAPA) was synthesized through acid base reaction and grown as single crystals by solvent evaporation method. Single crystal XRD analysis showed that EDAPA crystallizes in orthorhombic system with Cmca as space group. The formation of charge transfer complex during the reaction of ethylenediamine and picric acid was strongly evident through the recorded Fourier Transform Infra Red (FTIR), Raman and Nuclear Magnetic Resonance (NMR) spectrum. Thermal (TG–DTA and DSC) curves indicated that the material possesses high thermal stability with decomposition temperature at 243 °C. Optical (UV–Visible-NIR) analysis showed that the grown crystal was found to be transparent in the entire visible and NIR region. Z-scan studies with intense short pulse (532 nm, 5 ns, 100 µJ) excitations, revealed that EDAPA exhibited two photon absorption behaviour and the nonlinear absorption coefficient was found to be two orders of magnitude higher than some of the known optical limiter like Cu nano glasses. EDAPA exhibited a strong optical limiting action with low limiting threshold which make them a potential candidate for eye and photosensitive component protection against intense short pulse lasers.

Optical quality single crystals of ethylenediaminium (2,4-dinitrophenolate) [EDA(2,4)DNP] were grown by solvent evaporation method for optical limiting applications against intense ultrashot pulse lasers. Single crystal XRD showed that the material crystallizes in monoclinic system with centric space group P 2 1 / C . The crystal packing diagram was elucidated for the first time in literature and it revealed six hydrogen bonds played a very important role in stabilizing the structure. A bifurcated hydrogen bond was also observed between ethylenediamminium and dinitrophenolate ions. The formation of charge transfer complex during the reaction of ethylenediamine and 2,4-dinitrophenol was strongly evident through the vibrational spectroscopic studies. TG–DTA and DSC curves indicate that the material exhibited strong decomposition at 224 °C. Ground state absorption analysis showed that the grown crystals possess absorption maxima in UV region (270 nm, 346 nm) and wide optical transmittance window (480–1200 nm) in the entire visible and NIR region. Measurement of two photon absorption (2PA) and optical limiting response by Z-scan technique under nanosecond pulse excitation was reported. Hence EDA(2,4)DNP with high 2PA coefficient (0.79 ± 0.04 × 10 −10 m/W) and low limiting threshold (2.40 ± 0.05 × 10 12 W/m 2 ) will be a potential candidate for optical limiting applications like eye and sensor protection against short pulse lasers that are well spread in human interactive sectors.

Nonlinear optical single crystal of L-Proline trichloroacetate (L-PTCA) was successfully grown by Slow Evaporation Solution Technique (SEST). The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm the structure. From the single crystal XRD data, solid state parameters were determined for the grown crystal. The crystalline perfection has been evaluated using high resolution X-ray diffractometer. The frequencies of various functional groups were identified from FTIR spectral analysis. The percentage of transmittance was obtained from UV Visible spectral analysis. TGA-DSC measurements indicate the thermal stability of the crystal. The dielectric constant, dielectric loss and ac conductivity were measured by the impedance analyzer. The DC conductivity was calculated by the cole-cole plot method.

Gamma bis glycinium oxalate (GBGOx) crystal was synthesized and grown by slow evaporation solution technique. The structure of pure GBGOx crystal has been examined by single crystal X-ray diffraction analysis. The confirmation with single crystal XRD reveals that the crystal belongs to monoclinic system with space group C 2 . The FTIR spectrum was recorded to identify the expected functional groups. UV–vis-spectrum shows the lower cut off wavelength and 80% of transmittance in the UV–vis region. The photoluminescence measurement shows that the material is suitable for photonic devices. Preliminary measurement of green light emission using Kurtz powder technique indicates that their second harmonic generation (SHG) efficiency. The microhardness analysis revealed that the grown crystal belongs to soft material category. The encouraging results show that the GBGOx crystals have great potential applications in optical devices.

Single crystal of l -alanine cadmium chloride (LACC) has been grown by the conventional seed suspended technique. The grown crystals were subjected to various characterizations such as powder XRD, FTIR, UV–vis, second and third harmonic generation measurements. The structure of pure LACC crystal has been examined by powder X-ray diffraction analysis. The confirmation with single crystal XRD reveals that the crystal belongs to monoclinic system with space group C 2 . The FTIR spectrum was recorded to identify the expected functional groups and the molecular structure was confirmed by 1 H NMR spectrum. Dielectric measurements reveal that the grown crystals have very low dielectric loss. UV–vis-spectrum shows the lower cut off wavelength at 245 nm and transparency above 95% in the UV–vis region. The optical band gap was determined to be 5.12 eV. Preliminary measurement of green light emission using Kurtz powder technique indicates that their second harmonic generation (SHG) efficiency. The third order nonlinear optical parameters such as nonlinear refractive index ( n 2 ), nonlinear absorption coefficient ( β ) and third order susceptibility ( χ 3 ) are found to be in the order of 2.4233 × 10 −14 cm 2 /W, 0.2252 × 10 −4 cm/W, 0.9134 × 10 −15 esu, respectively by Z scan measurement. The encouraging results show that the LACC crystals have great potential applications in optical devices.

2-Amino-5-nitropyridinium halides (2A5NPBr)/(2A5NPCl) were synthesized by dissolving 2-amino-5-nitropyridine in hydrobromic/hydrochloric acid. Nanoparticles of 2A5NPBr and 2A5NPCl were attained by hydrothermal method. For comparison and estimation of mechanical properties, single crystals of the samples were grown by slow evaporation process. SEM analysis shows the formation of nanoparticles of 2A5NPBr and 2A5NPCl with average grain size of 50 and 100[Formula: see text]nm, respectively. UV-Vis analysis reveals that the materials possess low cut-off wavelength and a wide optical transmission window. By Vickers test, the Meyer index (n) was estimated to be 1.33 for 2A5NPBr and 2.49 for 2A5NPCl crystals. The SHG efficiency of 2A5NPBr and 2A5NPCl nanoparticles was calculated to be 1.5 and 4.3 times that of well known NLO material KDP. The role of cations in demonstrating the desired NLO properties were discussed in detail.

ZnS‐MgS nanocomposites was successfully prepared by the microwave assisted solvothermal method using a domestic microwave oven. The prepared sample was annealed at 100 °C for 1 hr to improve the ordering. Grain sizes and lattice parameters were determined by carrying out X‐ray powder diffraction measurements. Scanning electron microscopy (SEM) shows the morphology. AC electrical measurements were carried out on pelletised samples at various temperatures ranging from 40–150 °C. Results of the present study reveal that the space charge contribution plays a significant role in the charge transport process and polarizability.