scholarly journals Pitfalls in the Evaluation of X-ray Diffraction Line Shape

1988 ◽  
Vol 41 (2) ◽  
pp. 237 ◽  
Author(s):  
Gerhard Zorn
Keyword(s):  
Fourier Transform ◽  
Computer Simulations ◽  
Line Shape ◽  
Fourier Transformation ◽  
Step Width ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sampling Points ◽  
The Fourier Transform ◽  
Reliable Basis

The sources of errors in the analysis of X-ray diffraction profiles are described, and recipes are given to minimise or eliminate these errors. It is proposed that a sample at high temperatures is used as a standard. The influence of measurement statistics on the Fourier transform of deconvoluted functions is demonstrated through computer simulations. The necessity for smoothing procedures is stressed. It is shown how the parameter step width, number of sampling points, and position of origin for the Fourier transformation can be optimised, and thus a reliable basis can be created for the interpretation of the Fourier transform in terms of crystallite size, size distribution, and micros train.

A study of a long-spacing mica-like mineral

Clay Minerals ◽  
1966 ◽  
Vol 6 (4) ◽  
pp. 261-281 ◽  
Author(s):  
W. F. Cole
Keyword(s):  
Fourier Transform ◽  
Layer Structure ◽  
Compositional Variation ◽  
X Ray Diffraction ◽  
Transform Method ◽  
X Ray ◽  
Single Complex ◽  
New Interpretation ◽  
The Fourier Transform ◽  
Diffraction Effects

AbstractAn interstratified clay mineral from Surges Bay, Tasmania, described by Cole & Carthew (1953) as containing a random stacking of illite and montmorillonite in the ratio of 3:2 and a regular stacking of illite and montmorillonite in the ratio of 1 : 1 is re-examined, after purification, and a new interpretation is made of the X-ray diffraction effects in terms of a single complex stacking model. The Fourier transform method of analysis used with an appropriate layer structure factor shows that the interstratification is produced by a three component stacking of 18% single mica layers (A), 10% double mica layers (ĀĀ) and 72% allevardite-like layers (ĀB̄) in which the A and ĀĀ layers are never together. This leads to the conclusion that the near regular interstratification of the mineral is due to structural and/or compositional variation from layer to layer within the parent crystals as suggested by Sudo, Hayashi & Shimoda (1962) to explain similar mineral types occurring in Japan.

Optimization of Stepsize in X-Ray Powder Diffractogram Collection

1988 ◽  
Vol 3 (1) ◽  
pp. 32-38 ◽  
Author(s):  
David G. Cameron ◽  
Ernest E. Armstrong
Keyword(s):  
Fourier Transform ◽  
Fourier Transforms ◽  
X Ray Diffraction ◽  
Step Size ◽  
Reasonable Estimate ◽  
X Ray ◽  
Fourier Transform Methods ◽  
Step Interval ◽  
The Fourier Transform ◽  
Selection Of

AbstractFourier transform methods of smoothing and interpolation are applied to X-ray diffraction data. It is shown that, frequently, too small a step size is used. Major gains are to be expected by selection of the optimum step size and use of these methods.A comparison of Fourier transforms of diffractograms of quartz measured between 67 and 69° 2θ, collected at varying step intervals (0.1 to 0.01° 2θ) was used to illustrate these applications. By examining the Fourier transform of the diffractogram and noting where it decays to die baseline, a reasonable estimate of the optimal step interval can be obtained. In addition, Fourier interpolation can be used to enhance the appearance of the diffractogram, approximating a continuous plot.

A NANOSTRUCTURED POLYMORPH OF μ-OXOBIS(PHTHALOCYANINATOIRON(III)) STUDIED BY ANGULAR AND ENERGY DISPERSIVE X-RAY DIFFRACTION

NANO ◽  
2007 ◽  
Vol 02 (02) ◽  
pp. 121-128 ◽  
Author(s):  
ROBERTO MATASSA ◽  
PAOLO BALLIRANO ◽  
MARIA PIA DONZELLO ◽  
CLAUDIO ERCOLANI ◽  
CLAUDIA SADUN ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Rietveld Method ◽  
Energy Dispersive ◽  
Structural Function ◽  
X Ray Diffraction ◽  
New Approach ◽  
X Ray ◽  
The Fourier Transform

A new approach of X-ray diffraction was used to investigate the nanostructured μ-Oxo(2) polymorph of μ-oxo-bis(phthalocyaninatoiron(III)), [ PcFe – O – FePc ]. The packing of the dinuclear units was determined by the Rietveld method on Angular Dispersive X-ray Diffraction (ADXD) data, whereas the intramolecular geometry was optimized by Energy Dispersive X-ray Diffraction (EDXD) exploiting the peculiar strength of those techniques. The dimension of the nanoparticles was estimated from the Fourier transform of the EDXD experimental structural function.

scholarly journals Regioselective Approach to Characterizing Increased Edge Availability in Layered Crystal Materials following Layer Expansion: Reaction of Kaolinite with Octadecyltrimethylammonium Salts

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 588
Author(s):  
Shingo Machida ◽  
Ken-ichi Katsumata ◽  
Atsuo Yasumori
Keyword(s):  
Fourier Transform ◽  
Mass Loss ◽  
Nitrogen Content ◽  
Infrared Spectra ◽  
Layered Crystal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermogravimetric Curve ◽  
Diffraction Patterns ◽  
The Fourier Transform

In this paper, the regioselective reactions of kaolinite and methoxy-modified kaolinite (MeO-Kaol), methanol-expanded kaolinite, with octadecyltrimethylammonium salts are compared. This study mainly concerns the reactions of kaolinite or MeO-Kaol with octadecyltrimethylammonium chloride (C18TAC) in methanol and the subsequent exhaustive washing of the resultant products with ethanol. X-ray diffraction patterns of the products reveal no intercalation of C18TAC between pristine kaolinite layers. Additionally, intercalation and subsequent deintercalation of C18TAC proceed in the product using MeO-Kaol. In the Fourier-transform infrared spectra, the intensities of CH2 stretching bands of the product prepared using MeO-Kaol drastically increase compared to those using kaolinite. In addition, CH2 stretching bands of the product using kaolinite are hardly observed without enlarging the spectrum. The product using MeO-Kaol also displays mass loss in the range of 200–300 °C in the thermogravimetric curve and a nitrogen content with 0.15 mass% estimated using the CHN analysis. These results therefore demonstrate an increase in the available reactive edges in the layered crystal material following an expansion of the stacked layers.

Röntgen-Beugungsuntersuchungen an Bi-In-Schmelzen / X-Ray Diffraction Experiments with Bi-In-melts

1981 ◽  
Vol 36 (2) ◽  
pp. 150-153 ◽  
Author(s):  
R. Bek ◽  
E. Nold ◽  
S. Steeb
Keyword(s):  
Fourier Transform ◽  
Liquidus Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coordination Numbers ◽  
Structure Factors ◽  
Concentration Dependency ◽  
The Fourier Transform

Abstract Using MoK α-radiation and a θ-θ diffractometer from molten In and Bi as well as six molten Bi-In alloys (8; 22; 27; 33.3; 50; and 77 at % Bi) intensity curves were obtained at 10 °C above the liquidus temperature. The measurements were performed in the q-region up to 14.5 Å-1. From the Fourier transform of the structure factors coordination numbers NItot and radii rItot were obtained. The concentration dependency of NItot and rItot leads to the conclusion, that the Bi-In melts belong to the compound forming melts.

Thermal and Structural of Methyl Cellulose

2014 ◽  
Vol 979 ◽  
pp. 307-310 ◽  
Author(s):  
W. Siriprom ◽  
S. Kongsriprapan ◽  
K. Teanchai
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermo Gravimetric Analysis ◽  
Methyl Cellulose ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Biodegradable Film ◽  
Thermo Gravimetric ◽  
X Ray ◽  
The Fourier Transform

The present study aims to investigate the physicochemical properties of the methyl cellulose. The information of this investigate has been used to reference in preparing biodegradable film. It was observed that the Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy show the hydrogen bond’s formation and the Energy Dispersive X-Ray Fluorescence (EDXRF) show the chemical and level of the composition element, which Copper (Cu) has the highest accumulate. Another that, the XRD spectra which investigated by X-Ray Diffraction (XRD) show the methyl cellulose had lowered crystalline. Another that, the Thermo-Gravimetric Analysis (TGA) was used to investigate the effect of heating and influence of thermal.

PREPARATION AND STRUCTURAL CHARACTERIZATION OF NANOCRYSTALLINE Zn–Cu–Cr FERRITES WITH Gd SUBSTITUTION

2010 ◽  
Vol 24 (27) ◽  
pp. 5409-5416 ◽  
Author(s):  
JING JIANG ◽  
CHAOCHAO CHEN ◽  
LUNHONG AI
Keyword(s):  
Fourier Transform ◽  
Spinel Structure ◽  
Remanent Magnetization ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Magnetic Parameters ◽  
The Fourier Transform

Nanocrystalline spinel Zn – Cu – Cr ferrites with Gd substitution were prepared by a rheological phase reaction method. By means of the Fourier transform infrared (FTIR) spectra, Raman spectra, and X-ray diffraction (XRD), the cubic spinel structure of samples had been confirmed. The magnetic parameters such as saturation magnetization, remanent magnetization and coercivity can be tailored by controlling the content of substituting Gd ions.

scholarly journals The modulus of the Fourier transform on a sphere determines 3-dimensional convex polytopes

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Konrad Engel ◽  
Bastian Laasch
Keyword(s):  
Fourier Transform ◽  
Convex Polytopes ◽  
Convex Polytope ◽  
X Ray Diffraction ◽  
X Ray ◽  
3 Dimensional ◽  
Empty Intersection ◽  
Open Set ◽  
Ewald Sphere ◽  
The Fourier Transform

Abstract Let 𝒫 and P ′ \mathcal{P}^{\prime} be 3-dimensional convex polytopes in R 3 \mathbb{R}^{3} and S ⊆ R 3 S\subseteq\mathbb{R}^{3} be a non-empty intersection of an open set with a sphere. As a consequence of a somewhat more general result it is proved that 𝒫 and P ′ \mathcal{P}^{\prime} coincide up to translation and/or reflection in a point if | ∫ P e - i ⁢ s ⋅ x ⁢ dx | = | ∫ P ′ e - i ⁢ s ⋅ x ⁢ dx | \bigl{\lvert}\int_{\mathcal{P}}e^{-i\mathbf{s}\cdot\mathbf{x}}\,\mathbf{dx}\bigr{\rvert}=\bigl{\lvert}\int_{\mathcal{P}^{\prime}}e^{-i\mathbf{s}\cdot\mathbf{x}}\,\mathbf{dx}\bigr{\rvert} for all s ∈ S \mathbf{s}\in S . This can be applied to the field of crystallography regarding the question whether a nanoparticle modelled as a convex polytope is uniquely determined by the intensities of its X-ray diffraction pattern on the Ewald sphere.

A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

1982 ◽  
Vol 40 ◽  
pp. 722-723 ◽  
Author(s):  
R. Gronsky
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Computer Simulations ◽  
Structural Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

PENGGUNAAN TiO2 PARTIKEL NANO HASIL SINTESIS BERBASIS AIR MENGGUNAKAN METODA SOL-GEL PADA BAHAN KAPAS SEBAGAI APLIKASI UNTUK TEKSTIL ANTI UV

Arena Tekstil ◽  
2013 ◽  
Vol 28 (1) ◽  
Author(s):  
Maya Komalasari ◽  
Bambang Sunendar
Keyword(s):  
Fourier Transform ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sol Gel ◽  
Crosslinking Agent ◽  
X Ray Diffraction ◽  
Nano Tio2 ◽  
X Ray ◽  
Infra Red ◽  
Scanning Electron

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.

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