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The optimized [Na0.5Bi0.5−x]0.94SmxBa0.06Ti0.98W0.02O3 (i.e., NBBTW:xSm) was synthesized using conventional solid-state reactions. The structural parameters of NBBTW:xSm were revealed by PXRD and related to the Rietveld refinement. The proposed ceramic system keeps the phase structure in which the rhombohedral (R) and tetragonal (T) phases coexist due to the doping of Sm3+ and W3+ ions. The samples are likely MPB compositions, as evidenced by the SAED patterns confirming the presence of R3c and P4mm phases. The luminescence characteristics of the resulting system show a dominant absorption peak at 407 nm. This is consistent with the near UV emission of LEDs available on the market. Also, the introduction of Sm3+ ions in the NBBTW grid increases the grain size, making the ceramic system larger and more stable in the antiferroelectric region. Joncher's law of power is valid for the AC conductivity spectrum, and the activation energy (Ea) associated with relaxation and conductivity mechanism has been calculated. These results show that Sm3+ additions to NBBTW have improved their electrical and luminescence characteristics more than NBBT, making them attractive for multifunctional applications. [ABSTRACT FROM AUTHOR]

The geometries, electrostatic potential, Mulliken charge analysis, Natural Bond Orbital analysis and polarizabilities of propyl-para-hydroxybenzoate were calculated using B3LYP functional with 6-311++G(d,p) basis set. The calculated geometries are well matched with the experimental values. The Mullliken atomic charge analysis shows that the eventual charges are contained in the molecule. The NBO analysis explains the intramolecular charge transfer in the PHB molecule. The bonding features of the molecule were analyzed with the aid of Hirshfeld surface analysis. The frontier molecular orbital analysis showed the charge transfer obtained within the molecule. The calculated hyperpolarizability of the PHB molecule was 6.977E −30 esu and it was 8.9 times that of standard urea molecule. [ABSTRACT FROM AUTHOR]

The temperature oscillation method was used to synthesize dense single-phase polycrystalline AgGaS 2 from high purity elements. AgGaS 2 single crystal of 8 mm diameter and 45 mm length, free of voids and crack was obtained by the descending ampoule with steady ampoule rotation method using the synthesized polycrystalline charge. The grown crystal was subjected to powder X-ray diffraction and single crystal X-ray diffraction. The AgGaS 2 has been studied using differential scanning calorimetry (DSC) technique. The single crystal has high transmission of 75% in the Mid IR region. The band gap energy was calculated using absorption spectrum. The stoichiometric composition of AgGaS 2 was measured using energy dispersive spectrometry (EDAX). The structural and compositional uniformities of AgGaS 2 were studied using micro-Raman scattering spectroscopy at room temperature. The photoluminescence behavior of AgGaS 2 has been analyzed. It shows the maximum emission at 538 nm. The resistivity of the grown single crystal has been measured. [ABSTRACT FROM AUTHOR]

Single crystal of the ternary semi-conductor AgInSe 2 has been grown by Bridgman technique. The AgInSe 2 crystal crystallizes in the tetragonal chalcopyrite structure. Using melt temperature oscillation method polycrystalline charge was synthesized. The synthesized charge was subjected to powder X-ray diffraction analysis. Thermal property of AgInSe 2 was analyzed using differential scanning calorimetry (DSC) technique. The melting and solidification temperature is 777 °C and 761 °C respectively. The synthesized polycrystalline charge was employed to grow AgInSe 2 single crystals. The grown crystal was confirmed by single crystal X-ray diffraction. The crystal exhibits 60% transmission in the Infrared region. The stoichiometric composition of AgInSe 2 was confirmed by Energy dispersive X-ray analysis (EDAX). The electrical properties of the crystal were studied by Hall Effect measurements and photoconductivity. [ABSTRACT FROM AUTHOR]

Abstract: The polycrystalline charges were successfully synthesized from high purity elemental starting materials by the vapor transport method with the mechanical and melt temperature oscillation. High pure, single phase, free of voids and crack-free AgGaSe2 single crystals have been grown by the vertical Bridgman technique with steady ampoule rotation. The structural perfection of the grown crystals has been analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. AgGaSe2 has been studied using differential scanning calorimetry (DSC) technique. The stoichiometric composition of AgGaSe2 was measured using energy dispersive spectrometry (EDS). The insignificant change in atomic percentages of Ag, Ga and Se along the ingot further reveals that the composition throughout its length is fairly homogeneous. The band gap and melting point along the length of the ingot are studied. The structural and compositional uniformities of AgGaSe2 were studied using micro-Raman scattering spectroscopy at room temperature. The insignificant change in the FWHM of the measured at different regions of the crystal further reveals that the composition throughout its length is fairly uniform. As grown single crystal shows very high IR transmission of ∼72% in the spectral range 4000–530cm−1. [Copyright &y& Elsevier]