A new method to evaluate the quality of single crystal Cu by an X-ray diffraction butterfly pattern method

A new method has been established for the preparation of C 2-oxidized 5,5-spiroacetals, which are key intermediates for the synthesis of the bis-spiroacetal moiety of the spirolides. A bridged orthoester was used as a masked carboxylic acid in the preparation of these bicyclic oxaspirolactones. The synthesis of chiral lactone (12), a building block for the synthesis of the spirolides, is also reported. The two chiral centres in lactone (12) were assembled by addition of a chiral crotyl borane to an aldehyde. The structure of lactone (12) was determined by single-crystal X-ray diffraction; orthorhombic space group P212121 (No. 19), a 12.437(2), b 23.881(4), c 7.545(1) Å, V 2240.9(5) Å3, R(F) 0.0460, and Rw(F) 0.0458.

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Soluble Pyridine Complexes Of The Ternary Gallium(III) Chalcogenide Halides (GaEX)3, With E = S, Se And X = Cl, Br

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-0803 ◽

2001 ◽

Vol 56 (8) ◽

pp. 711-718 ◽

Cited By ~ 4

Author(s):

Stefan D. Nogai ◽

Annette Schier ◽

Hubert Schmidbaur

Keyword(s):

Single Crystal ◽

Molecular Complexes ◽

Membered Ring ◽

New Method ◽

X Ray Diffraction ◽

X Ray ◽

Pyridine Ligands ◽

Ring Molecules ◽

Gallium Metal ◽

Convenient Preparation

The four ternary gallium(III) chalcogenide halides GaEX with E = S, Se and X = Cl, Br can be prepared a) from the binary gallium(III) chalcogenides Ga2E3 and halides Ga2X6, b) from gallium(I) tetrahalogallates(III) GafGaX4] and the chalcogen E, and c) from gallium metal and the dichalcogen dihalides E2X2. The new method c) was shown to be the most convenient preparation. The products are readily soluble in pyridine to give trinuclear molecular complexes [GaEX·Py]3 which are not volatile without decomposition, but can be purified by crystallization. The structures have been determined by single crystal X-ray diffraction techniques. The two chlorides are isostructural and show twisted tub-form six-membered ring molecules with the pyridine donors in axial positions. The two bromides are also isostructural, but with the pyridine ligands in two axial and one equatorial positions

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

Journal of Applied Crystallography ◽

10.1107/s0021889808008649 ◽

2008 ◽

Vol 41 (3) ◽

pp. 584-591 ◽

Cited By ~ 14

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.

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On the quality of the continuous rotation electron diffraction data for accurate atomic structure determination of inorganic compounds

Journal of Applied Crystallography ◽

10.1107/s1600576718007604 ◽

2018 ◽

Vol 51 (4) ◽

pp. 1094-1101 ◽

Cited By ~ 20

Author(s):

Yunchen Wang ◽

Taimin Yang ◽

Hongyi Xu ◽

Xiaodong Zou ◽

Wei Wan

Keyword(s):

Electron Diffraction ◽

Single Crystal ◽

Diffraction Data ◽

Structural Models ◽

Electron Diffraction Data ◽

Data Sets ◽

X Ray Diffraction ◽

X Ray ◽

Continuous Rotation

The continuous rotation electron diffraction (cRED) method has the capability of providing fast three-dimensional electron diffraction data collection on existing and future transmission electron microscopes; unknown structures could be potentially solved and refined using cRED data collected from nano- and submicrometre-sized crystals. However, structure refinements of cRED data using SHELXL often lead to relatively high R1 values when compared with those refined against single-crystal X-ray diffraction data. It is therefore necessary to analyse the quality of the structural models refined against cRED data. In this work, multiple cRED data sets collected from different crystals of an oxofluoride (FeSeO3F) and a zeolite (ZSM-5) with known structures are used to assess the data consistency and quality and, more importantly, the accuracy of the structural models refined against these data sets. An evaluation of the precision and consistency of the cRED data by examination of the statistics obtained from the data processing software DIALS is presented. It is shown that, despite the high R1 values caused by dynamical scattering and other factors, the refined atomic positions obtained from the cRED data collected for different crystals are consistent with those of the reference models refined against single-crystal X-ray diffraction data. The results serve as a reference for the quality of the cRED data and the achievable accuracy of the structural parameters.

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Single-crystal x-ray diffraction structures of covalent organic frameworks

Science ◽

10.1126/science.aat7679 ◽

2018 ◽

Vol 361 (6397) ◽

pp. 48-52 ◽

Cited By ~ 308

Author(s):

Tianqiong Ma ◽

Eugene A. Kapustin ◽

Shawn X. Yin ◽

Lin Liang ◽

Zhengyang Zhou ◽

...

Keyword(s):

Single Crystal ◽

Single Crystals ◽

Diffraction Data ◽

General Procedure ◽

Three Dimensional ◽

Electron Diffraction Data ◽

Covalent Organic Frameworks ◽

X Ray Diffraction ◽

X Ray

The crystallization problem is an outstanding challenge in the chemistry of porous covalent organic frameworks (COFs). Their structural characterization has been limited to modeling and solutions based on powder x-ray or electron diffraction data. Single crystals of COFs amenable to x-ray diffraction characterization have not been reported. Here, we developed a general procedure to grow large single crystals of three-dimensional imine-based COFs (COF-300, hydrated form of COF-300, COF-303, LZU-79, and LZU-111). The high quality of the crystals allowed collection of single-crystal x-ray diffraction data of up to 0.83-angstrom resolution, leading to unambiguous solution and precise anisotropic refinement. Characteristics such as degree of interpenetration, arrangement of water guests, the reversed imine connectivity, linker disorder, and uncommon topology were deciphered with atomic precision—aspects impossible to determine without single crystals.

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N2–O2 icing in single-crystal in-house X-ray diffraction experiments using an open-flow helium cryostat

Journal of Applied Crystallography ◽

10.1107/s1600576721006440 ◽

2021 ◽

Vol 54 (4) ◽

Author(s):

Boris A. Zakharov ◽

Ronald Miletich ◽

Nikita E. Bogdanov ◽

Elena V. Boldyreva

Keyword(s):

Single Crystal ◽

Gas Flow ◽

Condensation Rate ◽

Flow Conditions ◽

X Ray Diffraction ◽

Rapid Rotation ◽

Open Flow ◽

X Ray ◽

Helium Cryostat

This note reports a study of the coating of a crystal with `ice' at temperatures below 45 K during single-crystal in-house diffraction experiments when using an open-flow helium cryostat. The `ice' consists mainly of crystalline oxygen and nitrogen. This suggests completely different techniques for avoiding this type of icing compared with water icing. With appropriate choices of crystal mount, crystal position with respect to the nozzle and gas flow conditions, it is possible to avoid detectable condensation. However, sometimes this cannot be achieved in practice (poor diffraction from a smaller crystal, necessity of positioning the crystal in certain orientations to achieve desired data completeness, need to reduce helium consumption etc.). The problem of icing seems to be less common for powder experiments where the laminar gas flow is parallel to the capillary containing the sample, and for synchrotron experiments where the sample is comparatively small and almost continuously rotated, which facilitates the ice covering being removed by the gas flow. This last technique can in principle also be applied to single-crystal X-ray diffraction using laboratory diffractometers – periodic rapid rotation of the crystal can help to minimize any icing, but this technique will not work when the condensation rate is comparable to or faster than one frame of data collection. The coating around a sample crystal reduces the quality of the diffraction data, and the temperature at the sample below the coating may differ significantly from that at the cryostat nozzle reported by the instrument.

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Structural and Optical Property Investigations on Mg-Alloying in Epitaxial Zinc Oxide Films on Sapphire

MRS Proceedings ◽

10.1557/proc-595-f99w3.87 ◽

1999 ◽

Vol 595 ◽

Author(s):

A.K. Sharma ◽

C. Jin ◽

A. Kvit ◽

J. Narayan ◽

J.F. Muth ◽

...

Keyword(s):

Single Crystal ◽

Room Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Ion Channeling ◽

Zinc Oxide Films ◽

Transmission Electron ◽

Potential Applications ◽

Post Deposition

AbstractWe have synthesized single-crystal epitaxial MgZnO films by pulsed-laser deposition. High-resolution transmission electron microscopy, X-ray diffraction and Rutherford backscattering spectroscopy/ion channeling were used to characterize the microstructure, defect content, composition and epitaxial single-crystal quality of the films. In these films with up to ∼ 34 atomic percent Mg incorporation, an intense ultraviolet band edge photoluminescence at room temperature and 77 K was observed. The highly efficient photoluminescence is indicative of the excitonic nature of the material. Transmission spectroscopy revealed that the excitonic structure of the alloys was clearly visible at room temperature. Post-deposition annealing in oxygen reduced the number of defects and improved the optical properties of the films. The potential applications of MgZnO alloys in a variety of optoelectronic devices are discussed.

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Ion Beam Synthesis of Buried Single Crystal Erbium Silicide

MRS Proceedings ◽

10.1557/proc-201-319 ◽

1990 ◽

Vol 201 ◽

Cited By ~ 1

Author(s):

A. Golanski ◽

R. Feenstra ◽

M. D. Galloway ◽

J. L. Park ◽

S. J. Pennycook ◽

...

Keyword(s):

Single Crystal ◽

Ion Beam ◽

Annealing Process ◽

X Ray Diffraction ◽

Cross Sectional ◽

Single Crystalline ◽

X Ray ◽

Buried Layer ◽

High Doses

AbstractHigh doses (1016–1017/cm2) of 170 keV Er+ were implanted into single-crystal 〈111〉Si at implantation temperatures between 350°C and 520°C. Annealing at 800°C in vacuum following the implant, the growth and coalescence of ErSi2 precipitates leads to a buried single crystalline ErSi2 layer. This has been studied using Rutherford backscattering/channeling, X-ray diffraction, cross-sectional TEM and resistance versus temperature measurements. Samples implanted at 520°C using an Er dose of 7 × 1016/cm2 and thermally annealed were subsequently used as seeds for the mesocpitaxial growth of the buried layer during a second implantation and annealing process. Growth occurs meso-epitaxially along both interfaces through beam induced, defect mediated mobility of Er atoms. The crystalline quality of the ErSi2 layer strongly depends on the temperature during the second implantation.

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Crystals M2Ni (SO4)2.XH2O (M=Na, X=4; M=K, NH4, Rb, Cs, X=6): Crystal Structures, Spectrum and Thermal Stability Characterizations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.332-334.1687 ◽

2011 ◽

Vol 332-334 ◽

pp. 1687-1690

Author(s):

Xia Wang ◽

Ming Qing Xing

Keyword(s):

Single Crystal ◽

Crystal Structures ◽

Relative Size ◽

Diffraction Method ◽

Electron Transition ◽

X Ray Diffraction ◽

X Ray ◽

Single Crystal Structures ◽

Average Bond

Single crystal structures of M2Ni (SO4)2.XH2O (M=Na, X=4; M=K, NH4, Rb, Cs, X=6) were investigated using the single crystal X-ray diffraction method. They crystallize isotypic (space group P2 (1)/c). Many structure features exhibit regularity with the relative size of radius, such as a, b, c, V. But to ANSH, the regularity of average bond lengths of violets from others. Their optical transmission spectrums were recorded on PE-lambda 900 with performing wavelengths ranging from 200 to 1100 nm, they have the similar optical characters in tested wavelength range. This phenomenon arises from the electron transition of d orbits in the octahedral field. The similarity in optical spectrum is consistent with the comparability of structures. We also investigated the thermal-gravimetric quality of above single crystals under same experiment conditions. We found that the dehydration temperatures increase with increasing of radius of the M+ when M =K, Rb, Cs. When M=Na, the dehydration temperature (tdh) is above the others pronouncedly due to the specialty of structure. To NH4-, the so-called compound is also with exception of the regularity.

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Thermal properties of monoclinic crystal Er3+:Yb3+:Ca4YO(BO3)3

Journal of Applied Crystallography ◽

10.1107/s0021889806045407 ◽

2007 ◽

Vol 40 (1) ◽

pp. 125-132 ◽

Cited By ~ 22

Author(s):

W. W. Ge ◽

H. J. Zhang ◽

J. Y. Wang ◽

M. H. Jiang ◽

S. Q. Sun ◽

...

Keyword(s):

Single Crystal ◽

Czochralski Method ◽

X Ray Diffraction ◽

High Crystalline Quality ◽

Monoclinic Crystal ◽

Monoclinic System ◽

X Ray ◽

Rank Tensor ◽

Co Doped

A large Er3+–Yb3+co-doped yttrium calcium oxoborate [Er3+:Yb3+:Ca4YO(BO3)3, abbreviated as Er:Yb:YCOB] single crystal, with dimensions of 2.5 cm in diameter and 9.0 cm in length, has been grown along the crystallographicbaxis by the Czochralski method. X-ray powder diffraction results show that the as-grown Er:Yb:YCOB crystal belongs to the monoclinic system with space groupCm; the unit-cell constants area= 8.085,b= 16.048,c= 3.528 Å and β = 101.11°. The high crystalline quality of the as-grown single crystal was confirmed by high-resolution X-ray diffraction, which showed the full width at half-maximum of the rocking curves to be less than 20 arcseconds on the (060) and (\overline 201) diffraction planes. The measurement and calculation of the symmetrical second-rank tensor for the monoclinic crystal are described in detail in this paper. The principal coefficients of thermal expansion of the as-grown Er:Yb:YCOB crystal are αI= 11.95 × 10−6 K−1, αII= 9.20 × 10−6 K−1and αIII= 18.93 × 10−6 K−1over the temperature range 303.15–873.15 K. The specific heat of the crystal is 725.6 J kg−1 K−1at 328.15 K. The principal thermal conductivity parameters areKI= 2.882 W m−1 K−1,KII= 2.687 W m−1 K−1andKIII= 2.692 W m−1 K−1at 328.15 K.

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