Rapid growth of a long-seed KDP crystal

To reduce the seed length while maintaining the advantages of the cuboid KDP-type crystal, a long-seed KDP crystal with size $471~\text{mm}\times 480~\text{mm}\times 400~\text{mm}$ is rapidly grown. With almost the same high cutting efficiency to obtain third harmonic generation oriented samples, this long-seed KDP-type crystal can be grown with a shorter seed than that of the cuboid KDP-type crystal. The full width at half maximum of the high-resolution X-ray diffraction of the (200) crystalline face is 28.8 arc seconds, indicating that the long-seed KDP crystal has good crystalline quality. In the wavelength range of 377–1022 nm, the transmittance of the long-seed KDP crystal is higher than 90%. The fluence for the 50% probability of laser-induced damage (LID) is $18.5~\text{J}/\text{cm}^{2}$ (3 ns, 355 nm). Several test points survive when the laser fluence exceeds $30~\text{J}/\text{cm}^{2}$ (3 ns, 355 nm), indicating the good LID performance of the long-seed KDP crystal. At present, the growth of a long-seed DKDP crystal is under way.

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Polyhedral characteristics of the cosalite-type crystal structures

The Canadian Mineralogist ◽

10.3749/canmin.1900017 ◽

2019 ◽

Vol 57 (5) ◽

pp. 647-662

Author(s):

Sabina Kovač ◽

Predrag Dabić ◽

Aleksandar Kremenović ◽

Aleksandar Pačevski ◽

Ljiiljana Karanović ◽

...

Keyword(s):

Crystal Data ◽

Chemical Formula ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

X Ray ◽

Area Detector ◽

Octahedral Sites ◽

Distorted Octahedral ◽

Cation Substitutions ◽

Type Crystal

Abstract The crystal structure of cosalite from the Trepča orefield was refined in the orthorhombic space group Pnma [a = 23.7878 (9), b = 4.0566 (3), c = 19.1026 (8) Å, V = 1843.35 (17) Å3, Z = 2] from single-crystal data (MoKα X-ray diffraction, CCD area detector) to the conventional R1 factor 0.031 for 1516 unique reflections with I > 2σ(I). The chemical formula (Cu0.15Ag0.24)+(Fe0.19Pb7.20)2+(Bi7.06Sb1.06)3+S20, calculated on the basis of 20 S atoms per formula unit, was determined by WDX. The unit cell contains 18 + 2 symmetrically nonequivalent atomic sites: 10 occupied by S; two by pure Pb (Pb3 and Pb4); one by pure Bi (Bi1); two by a combination of Bi and small amounts of Sb (Bi2/Sb2, Bi4/Sb3); two by Pb and Bi, and in one of these also by a small amount of Ag [Me1 = Pb2 >> Bi5 > Ag1, Me3 = Pb1 >> Bi3]; and finally one site, Me2 (Bi6 >> □), is partly occupied by Bi and partly split into an additional two adjacent trigonal planar “interstitial positions”, Cu1 and Cu2, where small amounts of Cu, Ag, and Fe can be situated. All atoms are at 4c special positions at y = 0.25 or 0.75. The structure consists of slightly to moderately distorted MeS6 octahedra sharing edges, bicapped trigonal PbS8 coordination prisms, and fairly distorted Cu1S6 and Cu2S4 polyhedra. The effects of the cation substitutions, bond valence sums, and the polyhedral characteristics are compared with other published cosalite-type structures. Among known cosalite-type structures, the largest volume contraction is shown by sample 4 (Altenberg) and involves the replacement of large cations (Bi3+ and Pb2+) by the smaller Sb3+, as well as Cu+ and Ag+. These replacements are reflected in the variations of individual Me–S bond distances, which are accompanied by variations in average Me–S distances. The degree of polyhedral distortion, Δ, progressively increases for the four Bi-hosting sites of nine cosalite-type structures: Me2 < Bi2 < Bi1 < Bi4. The Bi4 and Me3 are the most and the Me1 and Me2 are the least distorted octahedral sites of the nine cosalite-type structures.

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Formation and Thermal Stability of Nd0.32Y0.68Si1.7 Layers Formed by Channeled Ion Beam Synthesis

MRS Proceedings ◽

10.1557/proc-514-191 ◽

1998 ◽

Vol 514 ◽

Cited By ~ 1

Author(s):

M. F. Wu ◽

A. Vantomne ◽

S. Hogg ◽

H. Pattyn ◽

G. Langouche ◽

...

Keyword(s):

Thermal Stability ◽

Ion Beam ◽

Hexagonal Structure ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Good Crystalline Quality ◽

Ion Beam Synthesis ◽

Thermal Stability Of

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.

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X-Ray Diffraction Studies on Alicyclic Saturated Discotic Liquid Crystals

Zeitschrift für Naturforschung A ◽

10.1515/zna-1987-0619 ◽

1987 ◽

Vol 42 (6) ◽

pp. 631-635 ◽

Cited By ~ 10

Author(s):

H. W. Neuling ◽

H. Stegemeyer ◽

K. Praefcke ◽

B. Kohne

Keyword(s):

Liquid Crystalline ◽

Optical Observations ◽

X Ray Diffraction ◽

X Ray ◽

Alkyl Chains ◽

New Class ◽

X Ray Scattering ◽

Oriented Samples ◽

Hexagonal Columnar

The discotic liquid crystalline phase of a new class of disc-like molecules (hexa-O-alkanoylscyllo- inositoles) is studied by small angle X-ray scattering, DSC and optical observations. Comparison of these three methods allows the determination of the structural arrangement. X-ray film exposures of oriented samples clearly demonstrate the hexagonal columnar ordered type of mesophases. A simple model calculation shows that the alkyl chains of neighbouring columns interpenetrate each other to a small extent.

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Effect of Laser Surface Modification on the Crystallinity of Poly(L-Lactic Acid)

Journal of Manufacturing Science and Engineering ◽

10.1115/1.3039519 ◽

2009 ◽

Vol 131 (5) ◽

Cited By ~ 16

Author(s):

Anubha Bhatla ◽

Y. Lawrence Yao

Keyword(s):

Lactic Acid ◽

Polymer Surface ◽

X Ray Diffraction ◽

Factors Affecting ◽

Laser Surface Modification ◽

Third Harmonic ◽

X Ray ◽

Annealing Conditions ◽

Kinetics Of

Crystallinity of semicrystalline polymers such as aliphatic homopolymer poly(L-lactic acid) (PLLA) affects their degradation and physical properties. In this paper, the effects of laser irradiation using the third harmonic of a Nd:YAG laser on the crystallinity, long-range order, and short-range conformations at the surface of PLLA films are investigated. The factors affecting the transformation are also studied. Detailed characterization of the effect of laser treatment is accomplished using microscopy, X-ray diffraction, and infrared spectroscopy. The cooling rates in the process and the spatial and temporal temperature profiles are numerically examined. The simulation results in conjunction with melting and crystallization kinetics of PLLA are used to understand the effect on sample crystallinity. The effects of laser fluence and annealing conditions on the crystallinity of the processed films are examined. Since degradation profiles depend on crystallinity, laser processing can potentially be used to achieve a modified spatially controlled polymer surface with promising applications such as controlled drug delivery.

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Infrared Spectroscopy and X-ray Diffraction Studies of Thermal Behavior and Lamella Structures of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) with PHB-Type Crystal Structure and PHV-Type Crystal Structure

Macromolecules ◽

10.1021/ma102723n ◽

2011 ◽

Vol 44 (8) ◽

pp. 2829-2837 ◽

Cited By ~ 29

Author(s):

Harumi Sato ◽

Yuriko Ando ◽

Hiroshi Mitomo ◽

Yukihiro Ozaki

Keyword(s):

Crystal Structure ◽

Infrared Spectroscopy ◽

Thermal Behavior ◽

X Ray Diffraction ◽

X Ray ◽

Type Crystal

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XRD Studies of Synthesized Bi2S3Crystalline Materials

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314094911 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C508-C508

Author(s):

Ishverbhai Patel ◽

Sneha Solanki

Keyword(s):

Solid State ◽

Crystallite Size ◽

Sodium Dodecyl ◽

Solvothermal Reaction ◽

Bismuth Sulfide ◽

Photovoltaic Devices ◽

X Ray Diffraction ◽

X Ray ◽

Standard Data ◽

Good Crystalline Quality

Bismuth sulfide preparation and its x-ray diffraction studies are reported in this paper. The author have synthesized Bi2Sx (x = 3.15, 3.45) compound material with different sulfur content by conventional high temperature solid state solvothermal reaction of bismuth and sulfur which conforms that the (121) preferred orientation with crystallite size ~30 nm and splitting of peaks due to orthorhombic structure matches well with the standard data and demonstrate good crystalline quality and structural homogeneity of synthesized powder.This paper also describes the synthesis and x-ray diffraction studies of bismuth sulfide powder via versatile precipitation technique . Bismuth sulfide powder was synthesized using thiourea and sodium dodecyl sulfate or in absence of any surfactant maintained at 800C for 12 h keeping pH of solution constant at 1.4. Synthesized powder was characterized by x-ray diffraction technique which indicates that surfactants play major role in synthesis of bismuth sulfide that conforms the crystallite size ~35 nm. The employed solid state solvothermal technique played an important role to progress the homogeneous reaction and preparation of pure and fine bismuth sulfide powder. The possible application of this material in photovoltaic devices is suggested.

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X-ray diffraction data and Rietveld refinement of CuGaxIn1-xSe2 (x=0.15 and 0.50)

Powder Diffraction ◽

10.1154/1.3478374 ◽

2010 ◽

Vol 25 (3) ◽

pp. 253-257 ◽

Cited By ~ 10

Author(s):

E. J. Friedrich ◽

R. Fernández-Ruiz ◽

J. M. Merino ◽

M. León

Keyword(s):

Rietveld Refinement ◽

Diffraction Data ◽

Powder Diffraction Data ◽

X Ray Diffraction ◽

X Ray ◽

Zinc Blende ◽

Metal Atoms ◽

Tetragonal Crystal ◽

Unit Cells ◽

Type Crystal

X-ray powder diffraction data for CuGa0.15In0.85Se2 and CuGa0.50In0.50Se2 are reported. Indexing of the X-ray diffraction powder pattern and the Rietveld refinement confirmed that these compounds crystallize in the tetragonal crystal system, with space group I-42d (No. 122) and lattice parameters of a=5.7528(2) Å and c=11.5225(3) Å for CuGa0.15In0.85Se2 and a=5.6847(1) Å and c=11.2817(1) Å for CuGa0.50In0.50Se2. The CuGaxIn1−xSe2 system presents the chalcopyrite type crystal structure (CuFeS2) and corresponds to two stacked zinc-blende unit cells. The metal atoms Cu, In, and Ga are regularly ordered in the unit cell. Every Se atom is tetrahedrally bonded to two Cu and two In and Ga atoms.

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Growth and Characterization of Benzimidazolium Salicylate: NLO Property from a Centrosymmetric Crystal

Advances in Optical Technologies ◽

10.1155/2015/206325 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 18

Author(s):

M. Amudha ◽

R. Rajkumar ◽

V. Thayanithi ◽

P. Praveen Kumar

Keyword(s):

Grown Crystal ◽

Wavelength Region ◽

Complex Salt ◽

X Ray Diffraction ◽

Monoclinic System ◽

Kdp Crystal ◽

Growth Technique ◽

X Ray ◽

Nlo Property

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.

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