Systematic centricity control using a chiral template: novel noncentrosymmetric polar niobium oxyfluorides and tantalum fluorides directed by chiral histidinium cations, [(L-hisH2)NbOF5], [(D-hisH2)NbOF5], [(L-hisH2)TaF7], and [(D-hisH2)TaF7]

2021 ◽  
Author(s):  
HeeJung Choi ◽  
Kang Min Ok
Keyword(s):  
Single Crystal ◽  
Slow Evaporation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Evaporation Method ◽  
Chiral Materials

Enantiomorphic histidinium cation-driven niobium and tantalum (oxy)fluoride compounds have been systematically synthesized through a slow evaporation method. Single-crystal X-ray diffraction indicates that all four reported chiral materials crystallize in the...

Growth and Characterization of Ammonium Dihydrogen Phosphate (ADP) Doped with H3BO3 Crystals Grown by Slow Evaporation Method

2016 ◽  
Vol 675-676 ◽  
pp. 573-576 ◽  
Author(s):  
Pratya Thongpanit ◽  
Weerapong Chewpraditkul ◽  
Nakarin Pattanaboonmee
Keyword(s):  
Boric Acid ◽  
Temperature Stability ◽  
Hardness Measurement ◽  
Dihydrogen Phosphate ◽  
Ammonium Dihydrogen Phosphate ◽  
Slow Evaporation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Evaporation Method

Ammonium dihydrogen phosphate (ADP) crystals is very interesting due to its nonlinear optical property. This study investigated on improving of material for academic use by adding boric acid to modify ADP crystals. Slow evaporation method in aqueous solutions of pure ADP and ADP doped with three concentrations of H3BO3 as 0.1, 1.0, 5.0 %wt were studied. The grown crystals were confirmed tetragonal structure by powder X-ray diffraction studies. The FTIR spectrum analysis presented various functional groups of boron in three conditions of doped ADP. TGA study was comfirned the temperature stability at 220 °C for both pure and doped ADP crytals. The machanical stress was analyzed by Vicker’s hardness measurement. The results of this analysis showed boric acid doped 1.0 %wt had superior machanical stress from 10 to 75 grams. ADP doped with boric acid at 1.0 %wt was accepted in all test properties.

scholarly journals The Role of Acidity in the Synthesis of Novel Uranyl Selenate and Selenite Compounds and their Structures

Crystals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 965
Author(s):  
Gabriel L. Murphy ◽  
Philip Kegler ◽  
Eike M. Langer ◽  
Evgeny V. Alekseev
Keyword(s):  
Single Crystal ◽  
The Novel ◽  
Orthorhombic Structure ◽  
Slow Evaporation ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Triclinic Structure ◽  
A Chain

Herein, the novel uranyl selenate and selenite compounds Rb2[(UO2)2(SeO4)3], Rb2[(UO2)3(SeO3)2O2], Rb2[UO2(SeO4)2(H2O)]·2H2O, and (UO2)2(HSeO3)2(H2SeO3)2Se2O5 have been synthesized using either slow evaporation or hydrothermal methods under acidic conditions and their structures were refined using single crystal X-ray diffraction. Rb2[(UO2)2(SeO4)3] synthesized hydrothermally adopts a layered 2D tetragonal structure in space group P42/ncm with a = 9.8312(4) Å, c = 15.4924(9) Å, and V = 1497.38(15) Å, where it consists of UO7 polyhedra coordinated via SeO4 units to create units UO2(SeO4)58− moieties which interlink to create layers in which Rb+ cations reside in the interspace. Rb2[(UO2)3(SeO3)2O2] synthesized hydrothermally adopts a layered 2D triclinic structure in space group P1¯ with a = 7.0116(6) Å, b = 7.0646(6) Å, c = 8.1793(7) Å, α = 103.318(7)°, β = 105.968(7)°, γ = 100.642(7)° and V = 365.48(6) Å3, where it consists of edge sharing UO7, UO8 and SeO3 polyhedra that form [(UO2)3(SeO3)2O2] layers in which Rb+ cations are found in the interlayer space. Rb2[UO2(SeO4)2(H2O)]·2H2O synthesized hydrothermally adopts a chain 1D orthorhombic structure in space group Pmn21 with a = 13.041(3) Å, b = 8.579(2) Å, c = 11.583(2) Å, and V = 1295.9(5) Å3, consisting of UO7 polyhedra that corner share with one H2O and four SeO42− ligands, creating infinite chains. (UO2)2(HSeO3)2(H2SeO3)2Se2O5 synthesized under slow evaporation conditions adopts a 0D orthorhombic structure in space group Cmc21 with a = 28.4752(12) Å, b = 6.3410(3) Å, c = 10.8575(6) Å, and V = 1960.45(16) Å3, consisting of discrete rings of [(UO2)2(HSeO3)2(H2SeO3)2Se2O5]2. (UO2)2(HSeO3)2(H2SeO3)2Se2O5 is apparently only the second example of a uranyl diselenite compound to be reported. A combination of single crystal X-ray diffraction and bond valance sums calculations are used to characterise all samples obtained in this investigation. The structures uncovered in this investigation are discussed together with the broader family of uranyl selenates and selenites, particularly in the context of the role acidity plays during synthesis in coercing specific structure, functional group, and topology formations.

Growth of Ethyl-Para-Hydroxybenzoate Single Crystal and its Characterization

2012 ◽  
Vol 584 ◽  
pp. 121-125 ◽  
Author(s):  
N. Karunagaran ◽  
P. Ramasamy
Keyword(s):  
Single Crystal ◽  
Diffraction Analysis ◽  
Grown Crystal ◽  
Vickers Microhardness ◽  
Damage Threshold ◽  
Laser Damage Threshold ◽  
Solution Technique ◽  
Slow Evaporation ◽  
X Ray Diffraction ◽  
X Ray

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.

Electron Microscopy of Shock Loaded Polycrystalline Beryllium

1974 ◽  
Vol 32 ◽  
pp. 506-507 ◽  
Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens
Keyword(s):  
Electron Microscopy ◽  
Wave Propagation ◽  
Structural Change ◽  
Single Crystal ◽  
Diffraction Pattern ◽  
Shock Loading ◽  
Slip Systems ◽  
Compression Tests ◽  
X Ray Diffraction ◽  
X Ray

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.

Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

2003 ◽  
Vol 218 (5) ◽  
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören
Keyword(s):  
Crystal Structure ◽  
Inclusion Complex ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Type

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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