Synchrotron X-ray powder diffraction

TABLE 2 X-ray structural data for Sc< C82, Y >Cs2, and La Cs2 determined by synchrotron powder X-ray diffraction... 

Structure of RUF4. Data Collection. Synchrotron powder X-ray diffraction data were collected on a sample of RUF4 contained in a 0.5-... 

Wilkins S, Shekunov BY, York P. Theophylline ethylcellulose co-precipitates formed by solution enhanced dispersion by supercritical fluids (SEDS) and solvent co-evaporation—structural analysis by synchrotron powder X-ray diffraction. AAPS Pharm Sci 2001 3 1136. 

Miyasaka K, Neimark AV, T erasaki O Density functional theory of in sim synchrotron powder X-Ray diffraction on mesoporous crystab argon adsorption on MCM-41, J Phys Chem C 113(3) 791-794, 2009. 

Kastbjerg, S., Uvarov, C. A., Kauzlarich, S. M., Nishibori, E., Spackman, M. A., Iversen, B. B. (2011). Multi-temperature synchrotron powder x-ray diffraction study and hirshfeld surface analysis of chemical bonding in the thermoelectric zintl phase Ybi4MnSbn. Chemistry of Materials, 23, 3723-3730. 

The five years since last considering specifically recent developments in X-ray and neutron diffraction methods for zeolites [1] have witnessed substantial progress. Some techniques, such as high resolution powder X-ray diffraction using synchrotron X-rays, have blossomed from earliest demonstrations of feasibility to widespread and productive application. Others, such as neutron powder diffraction, have shown steady progress. For still others, notably microcrystal diffraction, a variety of circumstances have contributed to extended gestation periods. Additionally, opportunities scarcely considered earlier (such as single crystal Laue diffraction, and certain developments in computer simulations that complement diffraction work) now command broad attention and warrant the commitment of substantial further investment. 

In order to obtain detailed structure, a knowledge of diffraction intensities is essential, the intensities being related to the structure factor. Computer-controlled single-crystal X-ray diffractometers with structure (software) packages have made structure elucidation a routine matter. The availability of synchrotron X-radiation of continuously variable wavelength has made X-ray diffraction a still more powerful structural tool for the study of solids. A technique of great utility to solid state chemists is the Rietveld treatment of powder X-ray diffraction profiles (Rietveld, 1969 Manohar, 1983). Automated structure packages for the determination of unknown structures by this method are now commercially available (see section 2.2.3). In Fig. 2.1, we show a typical set of profile data. 

In the present report we describe initial syntheses in the M20-Si02-Sn02 H20 system. We illustrate how developments in characterization techniques can facilitate the identification of new phases in these types of systems. We mention use of synchrotron X-radiation in microcrystal diffraction experiments, full profile fitting of in-house powder X-ray diffraction data, and infrared and solid state 129Sn and 29Si nmr spectroscopies. 

FIGURE 5.17 Cellulose diffraction patterns. Top left synchrotron radiation x-ray diffraction pattern for cotton fiber bundle. The fiber was vertical and the white circle and line correspond to a shadow from the main beam catcher and its support. (Credit to Zakhia Ford.) Top right electron diffraction pattern of fragments of cotton secondary wall. The much shorter arcs in the top right figure are due to the good alignment and small number of crystallites in the electron beam. (Credit to Richard J. Schmidt.) Bottom a synthesized powder pattern for cellulose, based on the unit cell dimensions and crystalline coordinates of Nishiyama et al. [209]. (Credit to Zakhia Ford.) Also shown are the hkl values for the Miller indices. The 2-theta values are for molybdenum radiation instead of the more commonly used copper radiation. 

Newman, A. W., Stephens, R W., Morrison, H. G, Andres, M. C., Shatly, G. P. and Thomas, A. S. (1999). Quantitation of two polymorphic forms using Rietveld analysis, synchrotron XPRD and traditional XPRD. Presentation notes, pp. 85-96. Pharmaceutical Powder X-ray Diffraction Symposium, organized by International Centre for Diffraction Data, 27-30 Sep., 1999. [122, 123f, 124f]... 

OTT 97] OTTO J.W., On the peak profile in energy dispersive powder x-ray diffraction with synchrotron radiation , J. Appl. Cryst, vol. 30, p. 1008-1015,1997. 

The primary problem in structure solution from the powder x-ray diffraction pattern is the overlap of peaks in the pattern, which leads to severe ambiguities in determining the intensity of individual peaks and consequently the position of the atoms in the structure. High resolution x-ray diffraction patterns, which can be obtained using synchrotron x-radiation, are necessary for accurate structure determinations [92]. In addition to the x-ray diffraction patterns, neuron diffraction data have also been used for structure determination [99]. 

C) 4-chlorophenyl, and (D) 2-amlnophenyl derivatives. The powder X-ray diffraction data were collected using a synchrotron source. 

In Chapters I and 2, an introduction is made to the synchrotron Mossbauer spectroscopy with examples. Examples include the/ns/tu Mossbauer spectroscopy with synchrotron radiation on thin films and the study of deep-earth minerals. Investigations of in-beam Mossbauer spectroscopy using a Mn beam at the RIKEN RIBF is presented in Chapter 3. This chapter demonstrates innovative experimental setup for online Mossbauer spectroscopy using the thermal neutron capture reaction, Fe (n, y) Fe. The Mossbauer spectroscopy of radionuclides is described in Chapters 4-7. Chapter 4 gives full description of the latest analysis results of lanthanides Eu and Gd) Mossbauer structure and powder X-ray diffraction (XRD) lattice parameter (oq) data of defect fluorite (DF) oxides with the new defect crystal chemistry (DCC) Oq model. Chapter 5 reviews the Np Mossbauer and magnetic study of neptunyl(+l) complexes, while Chapter 6 describes the Mossbauer spectroscopy of organic complexes of europium and dysprosium. Mossbauer spectroscopy is presented in Chapter 7. There are three chapters on spin-state switching/spin-crossover phenomena (Chapter 8-10). Examples in these chapters are mainly on iron compounds, such as iron(lll) porphyrins. The use of Mossbauer spectroscopy of physical properties of Sn(ll) is discussed in Chapter I I. 

A powder X-ray diffraction pattern of this material, collected on a Rigaku diffractometer operated at 30 kV and 40 mA with CuKa radiation, is shown in Figure 3. This diffraction pattern is significantly different from ZnO, and bares no resemblance to that expected from a LDH pillared with the heptamolybdate anion (20,27). This diffraction pattern is almost identical to that of the Zn-LTM phase (22). A least squares refinement of the peak positions gave a hexagonal unit cell ofa = 6.104(9) A, and c = 21.69(9) A. The crystal structure of the Zn/Cu-LTM is a derivative of the Zn-LTM, whose structure solution is reported elsewhere (22). The structure of the Zn-LTM was solved by Rietveld refinement of an isostructural ammonium nickel molybdate, (NH4)HNi2(OH)2(Mo04)2, prepared by precipitation, whose own structure was determined, ab initio from powder synchrotron data (25). 

Synchrotron radiation based X-ray diffraction and scattering methods have found many uses in the study of structural developments of materials when exposed to external perturbations like pressure, chemical or mechanical changes. The well known method of powder X-ray diffraction (PXRD) or also Wide Angle X-ray Scattering (WAXS) hardly requires any introduction since it is a standard tool in many laboratories and we refer here to the many existing text books that describe the possibilities and limitations of this technique. ... 

To monitor the structure and crystallinity change of MOFs, powder X-ray diffraction is a convenient technique. More precise host-guest structural information could be obtained by synchrotron diffraction and single-crystal X-ray diffraction [97, 98]. Combination of other in-situ spectroscopic techniques can give more insightful structural information [99], especially for non-periodic stmctural alterations. 

Characterization of jS-hematin by powder X-ray diffraction techniques with both conventional and synchrotron illation indicates that the phase which results from equations 3 and 4 are sufficiently crystalline to give strong diffraction peaks out to 45 in 20 with Cu (X = 1.540598 A) radiation. The pattern obtained with synchrotron radiation (X = 1.7492 A) on beam line X7A at the National Synchrotron Light Source at the Brookhaven National Laboratory is shown in Figure 9. 

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