Growth of a bulk-size single crystal of sulphamic acid by an in-house developed seed rotation solution growth technique and its characterization

2017 ◽  
Vol 50 (3) ◽  
pp. 763-768 ◽  
Author(s):  
Sonia ◽  
N. Vijayan ◽  
Medha Bhushan ◽  
Kanika Thukral ◽  
Rishabh Raj ◽  
...  

A bulk sulphamic acid single crystal has been grown by a modified seed rotation technique. The lattice dimensions of the grown single crystal were confirmed using powder X-ray diffraction, and it was found that it crystallized in an orthorhombic structure with space groupPbca. The strain in the lattice was calculated by the Williamson–Hall equation. The crystalline perfection was examined by high-resolution X-ray diffraction and found to be extremely good (the single peak of the rocking curve having an FWHM of ∼8.0′′). The luminescence behaviour was recorded in the wavelength region between 400 and 630 nm using an Xe flash lamp which acts as an excitation source. The shock damage threshold was measured for the grown crystal in order to determine the mechanical capability of the title compound. The thermal parameter of sulphamic acid was calculated by photoacoustic spectroscopy.

1996 ◽  
Vol 11 (4) ◽  
pp. 804-812 ◽  
Author(s):  
Y. Namikawa ◽  
M. Egami ◽  
S. Koyama ◽  
Y. Shiohara ◽  
H. Kutami

Large YBa2Cu3O7−x (Y123) single crystals (larger than 13 mm cubed) have been grown along the c-axis reproducibly by the modified pulling method. The crystallinity of Y123 single crystal was investigated by x-ray diffraction and x-ray topography. Crystals grown from an MgO single crystal seed had some low angle subgrain boundaries which tilted 0.1–0.8° from each other. These grain boundaries originated from the seed crystal, and the subgrains were extended along the growth direction from the seed crystal. Y123 single crystals with no marked subgrains in the whole area were obtained by using Y123 single subgrain crystal seeds. FWHM of the x-ray rocking curve for the crystal so produced was about 0.14°, which was much better than the spectrum consisting of several separated peaks obtained from the previous crystals. Tc onset of the annealed sample was about 93.6 K, and the transition width was about 0.9 K. The low angle subgrain boundaries did not seem to be effective pinning centers for the magnetic flux.


1987 ◽  
Vol 20 (6) ◽  
pp. 522-528 ◽  
Author(s):  
S. E. G. Slusky ◽  
A. T. Macrander

A formula is derived for simulating rocking-curve measurements made with an X-ray diffractometer fitted with a four-reflection monochromator. The derivation is carried out both graphically and algebraically. Results of a simulation using this formula are then compared with experimentally obtained rocking curves. The rocking curves were obtained using a diffractometer with a four-reflection monochromator that uses 440 reflections from two channel-cut germanium crystals. The experimental data comprise 200, 400, 600, 511, 711, 622, 422 and 444 reflections from thick single-crystal indium phosphide grown by the vertical-gradient freeze technique. The simulated data correlate well with the experimental data, although the simulations consistently show somewhat higher reflectivities and narrower linewidths than the experiment, indicating the existence of broadening mechanisms not included in the simulation that are affecting the experiment.


2009 ◽  
Vol 23 (09) ◽  
pp. 1221-1227
Author(s):  
K. SELVARAJU ◽  
K. KIRUBAVATHI ◽  
S. KUMARARAMAN

Single crystals of 2-Naphthalenol (2N), new organic nonlinear optical (NLO) material, have been grown by slow evaporation solution growth technique at room temperature. The crystal system has been confirmed from the single crystal X-ray diffraction analysis. The functional groups were identified using FTIR spectroscopy. UV-vis-NIR spectrum showed absence of absorption in the wavelength region 400–1400 nm. The second harmonic generation efficiency is two times higher than that of standard potassium dihydrogen phosphate (KDP).


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
M. Amudha ◽  
R. Rajkumar ◽  
V. Thayanithi ◽  
P. Praveen Kumar

A new organic charge transfer molecular complex salt of benzimidazolium salicylate (BSL) single crystals was grown by the slow evaporation solution growth technique using methanol as a solvent at room temperature. The grown crystals were characterised by single crystal X-ray diffraction (XRD) which confirms that the crystal belongs to monoclinic system with the centrosymmetric space group P21/c. The crystalline perfection of the grown crystal was analyzed by high resolution X-ray diffraction (HRXRD). The presence of various functional groups was identified by FTIR spectrum. UV-Vis spectral study reveals that the BSL crystal is optically transparent in the wavelength region 342 nm–1100 nm. Dielectric measurements of the crystal at various frequencies were also determined. The mechanical properties of the grown crystal were assessed using Vickers microhardness testing. Nonlinear optical property of the crystal was confirmed using Kurtz and Perry powder technique and the SHG efficiency of the BSL crystal is 0.7 times greater than that of the standard KDP crystal.


2017 ◽  
Vol 6 (1) ◽  
pp. 62-68
Author(s):  
S. Vetrivel ◽  
R. U. Mullai ◽  
K. Kanagasabapathy ◽  
R. Aruljothi ◽  
V. Praveenkumar

Semiorganic optically transparent Bis(4-nitrobenzoate) tetraaquamanganese (II) dihydrate [Mn (p-NO2C6H4COO)2 (H2O)4]·2H2O (BNMD) single crystals were grown by slow evaporation technique at room temperature. Single crystal X-ray diffraction analysis was carried out to determine the lattice parameters of the crystal. Powder X-ray diffraction pattern was recorded and indexed for the structural confirmation. The crystalline quality was confirmed by HRXRD. The presence of functional group in the compound has been confirmed by FTIR analysis. UV-Visible transmission spectrum has been recorded to determine the cut-off wavelength region of the crystal. The Second Harmonic Generation of BNMD crystal was confirmed by Kurtz-Perry powder method using Nd:YAG laser and found to be 0.59 times that of KDP. The dielectric response of the crystal was also investigated and reported. The microhardness study reveals that the hardness number (Hv) increases with load. From the values of work hardening coefficients, it was concluded that BNMD crystal belong to the category of soft materials. Thermal studies were performed using differential thermal analysis (DTA).


2012 ◽  
Vol 584 ◽  
pp. 121-125 ◽  
Author(s):  
N. Karunagaran ◽  
P. Ramasamy

Ethyl-para-hydroxybenzoate (EHB) single crystals have been grown by slow evaporation solution technique (SEST) using methanol as a solvent. The grown crystal was subjected to single crystal X-ray diffraction analysis, confirming that the crystal belongs to monoclinic structure. The grown crystal was characterized by powder X-ray diffraction analysis. The functional groups present in the EHB crystal have been identified using FTIR spectrum analysis. The laser damage threshold of EHB crystal was measured. The mechanical strength of the grown EHB crystal was measured using Vickers microhardness, no cracks have been observed up to 100 g of load. The optical transparency of the grown EHB crystal has been measured by UV-Vis-NIR spectrophotometer. The refractive index of grown EHB single crystal is 1.6610. The dielectric permittivity and dielectric loss of the EHB single crystal were studied as function of frequency and temperature. The thermogravimetric analysis (TG) and differential thermal analysis (DTA) were studied. The melting point of EHB was 123°C. The luminescence behavior of EHB single crystal has been analyzed by photoluminescence analysis.


Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.


Author(s):  
W. Z. Chang ◽  
D. B. Wittry

Since Du Mond and Kirkpatrick first discussed the principle of a bent crystal spectrograph in 1930, curved single crystals have been widely utilized as spectrometric monochromators as well as diffractors for focusing x rays diverging from a point. Curved crystal diffraction theory predicts that the diffraction parameters - the rocking curve width w, and the peak reflection coefficient r of curved crystals will certainly deviate from those of their flat form. Due to a lack of curved crystal parameter data in current literature and the need for optimizing the choice of diffraction geometry and crystal materials for various applications, we have continued the investigation of our technique presented at the last conference. In the present abstract, we describe a more rigorous and quantitative procedure for measuring the parameters of curved crystals.The diffraction image of a singly bent crystal under study can be obtained by using the Johann geometry with an x-ray point source.


Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group


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