Growth defects and infrared spectra analysis of CePO4single crystals

2005 ◽  
Vol 38 (4) ◽  
pp. 675-677 ◽  
Author(s):  
Kunpeng Wang ◽  
Jianxiu Zhang ◽  
Jiyang Wang ◽  
Changshui Fang ◽  
Wentao Yu ◽  
...  
Keyword(s):  
Slow Cooling ◽  
Spectra Analysis ◽  
X Ray ◽  
Cell Parameters ◽  
Growth Defects ◽  
Cooling Method ◽  
Good Crystalline Quality ◽  
Growth Habits ◽  
Top Seeded Solution Growth

High-quality CePO4single crystals (monazite) were grown by the flux TSSG (top-seeded-solution growth) slow-cooling method. The X-ray powder diffraction pattern shows good crystalline quality of the crystals and the various peaks were assigned. The unit-cell parameters were calculated using theDICVOL90andTERORcomputer programs. The concentrations of all elements in the crystals were measured by electron probe microanalysis. Growth habits were deduced by the Bravais–Friedel Donnay–Harker (BFDH) method and macro-defects in the crystals are discussed. An infrared spectrum of the crystal was recorded in the frequency range of 300 to 1600 cm−1and all vibration frequency peaks were assigned.

Growth Studies and X-Ray Topographical Assessment of KTP

1993 ◽  
Vol 329 ◽  
Author(s):  
K B Hutton ◽  
R C C Ward ◽  
K W Godfrey
Keyword(s):  
Optical Transmission ◽  
Temperature Data ◽  
Potassium Titanyl Phosphate ◽  
X Ray Diffraction ◽  
Slow Cooling ◽  
X Ray ◽  
Growth Defects ◽  
Growth Method ◽  
Growth Quality ◽  
Top Seeded Solution Growth

AbstractDevice quality single crystals of potassium titanyl phosphate (KTP) have been grown using a top seeded solution growth method which incorporates a crystal weighing facility and which takes advantage of saturation temperatures well below the accepted transition temperature of this material. Weight and crucible temperature data are received and displayed on a monitoring computer in the form of a growth profile. Results obtained from the growth programme are discussed including the effect of very slow cooling (< 0.03 °C/hr) on the control of growth quality and a study of growth defects using x-ray diffraction topography carried out using synchrotron radiation. Variations on the standard K6P4O13 flux were investigated, including the addition of CeO2 to improve optical transmission and the use of K7P3O11 as an alternative growth solution.

scholarly journals Crystallization, optimization and preliminary X-ray characterization of a metal-dependent PI-PLC fromStreptomyces antibioticus

2012 ◽  
Vol 68 (11) ◽  
pp. 1378-1386 ◽  
Author(s):  
Michael R. Jackson ◽  
Thomas L. Selby
Keyword(s):  
X Ray Diffraction ◽  
Hanging Drop ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Streptomyces Antibioticus ◽  
Cell Parameters ◽  
Heavy Atoms ◽  
Hanging Drop Method

A recombinant metal-dependent phosphatidylinositol-specific phospholipase C (PI-PLC) fromStreptomyces antibioticushas been crystallized by the hanging-drop method with and without heavy metals. The native crystals belonged to the orthorhombic space groupP222, with unit-cell parametersa= 41.26,b= 51.86,c = 154.78 Å. The X-ray diffraction results showed significant differences in the crystal quality of samples soaked with heavy atoms. Additionally, drop pinning, which increases the surface area of the drops, was also used to improve crystal growth and quality. The combination of heavy-metal soaks and drop pinning was found to be critical for producing high-quality crystals that diffracted to 1.23 Å resolution.

EFFECT OF L-METHIONINE ON THE OPTICAL PROPERTIES OF POTASSIUM ACID PHTHALATE

2007 ◽  
Vol 21 (30) ◽  
pp. 2089-2094
Author(s):  
N. A. PAREY ◽  
M. A. SHAH
Keyword(s):  
Optical Properties ◽  
Slow Cooling ◽  
X Ray ◽  
Cooling Method ◽  
Bulk Single Crystals ◽  
Ft Ir ◽  
Ir Analysis ◽  
Potassium Acid Phthalate ◽  
Parameter Values ◽  
Acid Phthalate

The effect of L-methionine doping on the optical properties of potassium acid phthalate have been studied. Bulk single crystals of L-methionine-doped potassium acid phthalate (LMDKAP) were grown by a slow cooling method using a constant temperature bath. X-ray powder diffraction study has revealed the significant variation in the cell parameter values and the shift in peak positions, which confirms the presence of dopant in the sample. The UV-VIS cut off wavelength of LMDKAP was found to be 300 nm and it is slightly less than KAP. The presence of functional groups present in LMDKAP were confirmed through FT-IR analysis.

A Yb3+-doped NaY(WO4)2crystal grown by the Czochralski technique

2008 ◽  
Vol 41 (3) ◽  
pp. 584-591 ◽  
Author(s):  
Jiandong Fan ◽  
Huaijin Zhang ◽  
Wentao Yu ◽  
Haohai Yu ◽  
Jiyang Wang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structure Refinement ◽  
Czochralski Method ◽  
Point Of View ◽  
X Ray Diffraction ◽  
X Ray ◽  
Growth Habits ◽  
The Relationship

A transparent Yb3+:NaY(WO4)2single crystal with dimensions of 30 mm (diameter) × 40 mm has been grown by the Czochralski method. The high crystalline quality of the as-grown Yb3+:NaY(WO4)2crystals was confirmed by high-resolution X-ray diffraction. The effective segregation coefficients of elemental Yb, Na, Y and W in Yb3+:NaY(WO4)2were measured using the X-ray fluorescence method. Powder and single-crystal X-ray diffraction data of NaYb0.05Y0.95(WO4)2are reported. The structure refinement shows that NaYb0.05Y0.95(WO4)2crystallizes in the tetragonal space groupI41/a, witha=b= 5.2039 (2),c= 11.2838 (9) Å, α = β = γ = 90°,V= 305.57 (3) Å3andZ= 2. A series of possible growth faces (hkl) were determined from the crystal lattice and symmetry according to the Bravais–Friedel Donnay–Harker theory, and the relationship among crystal structure, growth habits and crystal morphology is discussed. In addition, the thermal properties of the crystal, including the specific heat, thermal expansion, thermal diffusion and thermal conductivity, were carefully investigated. The anisotropy of the crystal thermal conductivities is explained from the point of view of the crystal structure.

Effects of microgravity on the crystal quality of a collagen-like polypeptide

2000 ◽  
Vol 56 (1) ◽  
pp. 55-61 ◽  
Author(s):  
R. Berisio ◽  
L. Vitagliano ◽  
G. Sorrentino ◽  
L. Carotenuto ◽  
C. Piccolo ◽  
...  
Keyword(s):  
Space Shuttle ◽  
Protein Crystallization ◽  
Resolution Limit ◽  
Synchrotron Diffraction ◽  
Unit Cell Parameters ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Helical Molecules

(Pro-Pro-Gly)10 is one of the most widely studied collagen polypeptide models. Microgravity crystal growth of (Pro-Pro-Gly)10 was carried out in the Advanced Protein Crystallization Facility aboard the Space Shuttle Discovery during the STS-95 mission. Crystals were successfully grown in all experiments, using both dialysis and free-interface diffusion methods. The quality of the microgravity-grown crystals and of ground-grown counterparts was assessed by X-ray synchrotron diffraction. Microgravity-grown crystals exhibited a significant improvement in terms of dimensions and resolution limit. As previously reported, crystals were orthorhombic, space group P212121. However, the diffraction pattern showed weak reflections, never previously measured, that were consistent with new unit-cell parameters a = 26.9, b = 26.4, c = 182.5 Å. This allowed the derivation of a new model for the arrangement of the triple-helical molecules in the crystals.

scholarly journals Упругие и пьезоэлектрические параметры кристаллов гистидинфосфита L-Hist·H-=SUB=-3-=/SUB=-РО-=SUB=-3-=/SUB=-, полученные методом электромеханического резонанса

2018 ◽  
Vol 44 (3) ◽  
pp. 69
Author(s):  
Е.В. Балашова ◽  
Б.Б. Кричевцов ◽  
С.Н. Попов ◽  
П.Н. Брунков ◽  
Г.А. Панкова ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Elastic Moduli ◽  
Electromechanical Coupling ◽  
Elastic Compliance ◽  
X Ray Diffraction ◽  
Slow Cooling ◽  
X Ray ◽  
Cooling Method ◽  
Stretching Vibrations ◽  
Electromechanical Resonance

AbstractSingle crystals of L -histidine phosphite ( L -Hist · H_3РО_3) have been grown from aqueous solution by slow cooling method. The results of elemental analysis, of X-ray-diffraction studies of the crystal structure, and the habitus of the obtained crystals are given. The elastic and piezoelectric coefficients have been measured on the plates with the (010) natural faces by the method of electromechanical resonance for stretching vibrations in the temperature range 295–340 K. Elastic compliance values s _33 and s _22 and the corresponding elastic-moduli values, piezoelectric coefficients d _23 and d _22, coefficients of electromechanical coupling, and temperature coefficient of the resonance frequency are obtained. A comparison is given with other crystals, which are compounds of amino acids with phosphorous or phosphoric acid.

Synthesis and crystal structure of the lanthanum cyanurate complex La[H2N3C3O3]3 · 8.5 H2O

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Olaf Reckeweg ◽  
Falk Lissner ◽  
Thomas Schleid
Keyword(s):  
Interstitial Water ◽  
Cyanuric Acid ◽  
Dead Volume ◽  
Water Molecules ◽  
Ambient Conditions ◽  
Slow Cooling ◽  
Triclinic Space Group ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Cell Parameters

Abstract Single crystals of La[H2N3C3O3]3 · 8.5 H2O were obtained from stoichiometric amounts of as-precipitated La(OH)3 with cyanuric acid (CYA) [H3N3C3O3]3 in a boiling aqueous solution, followed by slow cooling and evaporation of water under ambient conditions. According to the X-ray structure analysis of the colorless and transparent crystals, La[H2N3C3O3]3 · 8.5 H2O adopts the triclinic space group P1 (no. 1) and exhibits the unit-cell parameters a = 987.24(7), b = 1110.97(8), c = 1179.81(9) pm, α = 113.716(2), β = 97.053(2), γ = 101.502(2)° for Z = 2. The CYA is singly deprotonated to give monoanions [H2N3C3O3]– which are O,N-coordinated to the La3+ cations. These dihdrogencyanurate anions are assembled in ribbons with two crystallographically different La3+ cations coordinating to either one or two different ligands, respectively. The coordination sphere of the La3+ cations is comprised of water molecules, and interstitial water molecules fill the dead volume of the crystals. The anionic ribbons are stacked to maximize the contact between the six-membered rings, showing distances of about 330 pm.

scholarly journals Crystallization and preliminary X-ray diffraction studies of the GhKCH2 motor domain: alteration of pH significantly improved the quality of the crystals

2012 ◽  
Vol 68 (7) ◽  
pp. 798-801
Author(s):  
Xinghua Qin ◽  
Ziwei Chen ◽  
Tao Xu ◽  
Ping Li ◽  
Guoqin Liu
Keyword(s):  
Crystal Morphology ◽  
Motor Domain ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Shanghai Synchrotron Radiation Facility ◽  
X Ray ◽  
Cell Parameters ◽  
Kinesin Superfamily

GhKCH2, a member of the kinesin superfamily, is a plant-specific microtubule-dependent motor protein from cotton with the ability to bind to both microtubules and microfilaments. Here, the motor domain of GhKCH2 (GhKCH2MD; amino acids 371–748) was overexpressed inEscherichia coli, purified and crystallized using the sitting-drop vapour-diffusion method. The pH of the crystallization buffer was shown to have a significant effect on the crystal morphology and diffraction quality. The crystals belonged to space groupP212121, with unit-cell parametersa= 60.7,b= 78.6,c= 162.8 Å, α = β = γ = 90°. The Matthews coefficient and solvent content were calculated as 2.27 Å3 Da−1and 45.87%, respectively. X-ray diffraction data for GhKCH2MD were collected on beamline BL17U1 at Shanghai Synchrotron Radiation Facility and processed to 2.8 Å resolution.

Effect of doping on crystalline quality of rubidium titanyl phosphate (RTP) crystals grown by the TSSG method

2014 ◽  
Vol 1698 ◽  
Author(s):  
Jianqiu Guo ◽  
Balaji Raghothamachar ◽  
Michael Dudley ◽  
Joan J. Carvajal ◽  
Ali Butt ◽  
...  
Keyword(s):  
Growth Process ◽  
Solution Growth ◽  
Crystalline Quality ◽  
Defect Structures ◽  
Growth Sector ◽  
High Quality ◽  
X Ray ◽  
Linear Defects ◽  
Top Seeded Solution Growth

ABSTRACTDefect structures in Rubidium Titanyl Phosphate (RTP) crystals (non-doped and doped) grown by the Top Seeded Solution Growth (TSSG) method were characterized using Synchrotron White Beam X-ray Topography. Main defects observed in non-doped crystals are growth sector boundaries while both growth sector boundaries and growth striations are observed in the Nb single doped and (Nb,Yb)-codoped crystals with relatively few linear defects such as dislocations. Results show that the overall crystalline quality is lowered as more doping elements are incorporated. Details of defect distributions are correlated with the growth process to facilitate high quality growth of doped RTP.

Improvement of X-ray powder diffraction patterns of the spin transition polymer [Fe(Htrz)3](ClO4)2⋅1.85H2O

2001 ◽  
Vol 16 (1) ◽  
pp. 37-41 ◽  
Author(s):  
E. Smit ◽  
B. Manoun ◽  
S. M. C. Verryn ◽  
D. de Waal
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Spin Transition ◽  
Powder Diffraction Data ◽  
High Quality ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Patterns

The effects of proper drying and grinding of [Fe(Htrz)3](ClO4)2⋅1.85H2O specimens on the quality of X-ray powder patterns are illustrated (Htrz=1H-1,2,4-Triazole). A procedure is suggested to achieve high-quality, reproducible X-ray powder patterns of the compound. The observed powder diffraction data of the compound are reported together with preliminary indices calculated for a monoclinic system with cell parameters a=15.8160 Å, b=20.6134 Å, c=13.0321 Å, β=103.83° and Volume=4125.633 Å3, with reliability factors: M15=10.4, F15=22.0 (0.0100; 68) and space group P21/m. This compound is very similar to the compound [Cu(Hyetrz)3](ClO4)2⋅3H2O and a comparison is made between the cell parameters of the two compounds

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