X-ray and Neutron Powder Diffraction

X-ray powder diffraction is routinely applied to identify products from syntheses. For phases that are known, powder diffraction pattern databases are available and can rapidly be searched for matches of peak position and intensity. For zeolitic solids (with tetrahedrally connected frameworks), the 

1 Structure Solution from Powder Diffraction Data 

Among the many successful structure solutions that have been achieved for tetrahedrally connected microporous solids from X-ray powder data alone are 

Advances in single crystal diffraction suggest that for structurally complex samples that do not show significant framework disorder, structure solution from microcrystals (or even nanocrystals - see the electron microscopy section) will be the most convenient route for solids that can be prepared as single crystals, even if they are less than 1000 pm in volume. Many aluminosilicate zeolites, however, can only be prepared as micron-sized crystals or may include stacking faults. As a result, continued developments in structure solution from X-ray powder diffraction are of great value. (See, for example, the Special Issue of Zeit. Krist., 219, 2004.) 

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The X-ray and neutron powder diffraction methods successfully use two approaches connected to extraction of intensities (see [14]) ... 

The goal of the present work is to synthesize of NbVCo hydride under high pressure (up to 200 MPa) and make structural analyses with X-ray and neutron powder diffraction. 

L. Pauling, Evidence from x-ray and neutron powder diffraction patterns that the so-called icosahedral and decagonal quasicrystals of MNA16 and other alloys are twinned cubic crystals. Proc. Natl. Acad. Sd. (USA) 84, 3951-3953 (1987). 

Because no single crystal of any binary rare-earth oxide fluoride has been obtained to date, computational efforts such as Rietveld analysis have been carried out to determine the crystal structure by means of X-ray and neutron powder diffraction. While... 

Figure 2.59. The electron (left) and nuclear (right) density distributions in the xOz plane of the unit cell of CeRhGcs calculated from x-ray and neutron powder diffraction data, respectively Figure 2.58). The contour of the unit cell is shown schematically as the rectangle under each Fourier map. The peaks correspond to various atoms located in this plane and are so marked on the figure. The volumes of the peaks are proportional to the scattering ability of atoms for x-rays the scattering power decreases in the series Ce(58 e) Rh(45 e) Ge(32 e) for neutrons, the coherent scattering lengths decrease in the reverse order Ge(8.19 fm)...

Table 7.18. Atomic parameters and interatomic distances (in A) after the completion of the combined Rietveld refinement based on both the x-ray and neutron powder diffraction data collected from NiMn02(0H) powder. The refined chemical composition is NiMnOs (OH)j where 8 = 0.62(5). The unit cell parameters are a = 2.86112(4), b = 14.6516(1), c =...

LHPM a Computer Program for Rietveld Analysis of X ray and Neutron Powder Diffraction Patterns, R. J. Hill, and C. J. Howard (1986) AAEC Report No. Ml 12 and QPDA A User Friendly, Interactive Program for Quantitative Phase and Crystal Size/Strain Analysis of Powder Diffraction Data, I. C. Madsen and R. J. Hill, Powder Diffr., 1990, 5, 195 199 A Rietveld analysis program RIETAN 98 and its applications to zeolites, F. Izumi and T. Ikeda, Mater. Sci. Forum, 2000, 321-324, 198 203 and F. Izumi, Development and Applications of the Pioneering Technology of Structure Refinement from Powder Diffraction Data, J. Ceram. Soc. Jpn., 2003, 111, 617 623... 

LHPM a Computer Program for Rietveld Analysis of X ray and Neutron Powder Diffraction Patterns, B. A. Hunter and C. J. Howard (February 2000), Lucas Heights Research Laboratories, Australian Nuclear Science and Technology Organisation and Rietica A visual Rietveld program, Brett Hunter, Int. Union Crystallogr., Commission Powder Diffr. Newsletter, 1998, No. 20, p. 21... 

In our case, the most widely used experimental techniques are conventional X-ray and neutron powder-diffractions.Very recent equipment using high-resolution devices (e.g., Brookhaven NSLS, Chess, Grenoble ILL, Orsay LURE, etc) have shown promise and are now widely exploited for the present purpose. Nevertheless, these installations are very sophisticated, and their accessibility is somewhat limited. However, conventional X-ray equipment is less useful, but it is essentially immediately available at most colleges, universities and... 

Space Groups and Crystal Packing Modes, p. 1337 X-Ray and Neutron Powder Diffraction, p. 1592... 

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