Crystal formation from glass, crystal structure refinement and thermal behavior of K1−xRbxBSi2O6boroleucite solid solutions from X-ray powder diffraction data

Crystal structure of the triclinic ternary phase Cr4(Al, Si)11 was investigated by full-profile Rietveld analysis of powder diffraction data. Four hundred eighty-four reflections were refined to a final RBragg value of 5.00%. Cr4(Al, Si)11 is isostructural to Mn4Al11. Silicon atoms enter into the structure by partially replacing aluminium on the Al(1) and Al(2) sites.

Download Full-text

Crystal Structure Refinement of Mg5Nb4O15and Mg5Ta4O15by Rietveld Analysis of Neutron Powder Diffraction Data

Journal of Solid State Chemistry ◽

10.1006/jssc.1998.7742 ◽

1998 ◽

Vol 137 (2) ◽

pp. 359-364 ◽

Cited By ~ 16

Author(s):

S. Pagola ◽

R.E. Carbonio ◽

M.T. Fernández-Dı́az ◽

J.A. Alonso

Keyword(s):

Crystal Structure ◽

Powder Diffraction ◽

Diffraction Data ◽

Structure Refinement ◽

Rietveld Analysis ◽

Neutron Powder Diffraction ◽

Crystal Structure Refinement ◽

Powder Diffraction Data ◽

Neutron Powder Diffraction Data

Download Full-text

Rietveld Structure Refinement of Metastable Lithium Disilicate Using Synchrotron X-Ray Powder Diffraction Data From the Daresbury SRS 8.3 Diffractometer

Powder Diffraction ◽

10.1017/s0885715600015566 ◽

1990 ◽

Vol 5 (3) ◽

pp. 137-143 ◽

Cited By ~ 6

Author(s):

R.I. Smith ◽

A.R. West ◽

I. Abrahams ◽

P.G. Bruce

Keyword(s):

Crystal Structure ◽

Powder Diffraction ◽

Diffraction Data ◽

Rietveld Method ◽

Structure Refinement ◽

Powder Diffraction Data ◽

X Ray ◽

New Instrument ◽

Diffraction Peaks

AbstractThe crystal structure of metastable Li2Si2O5, Fw = 150.05, has been refined by the Rietveld method using high resolution X-ray powder diffraction data recorded at the Daresbury Synchrotron Radiation Source on the new 8.3 diffractometer. Li2Si2O5, in keeping with many compounds of interest to the materials scientist, exhibits relatively broad diffraction peaks. It is important to establish the quality of crystal structure data that may be obtained from such materials on this new instrument. Various functions were used to model the peak shape from this instrument; a split-Pearson VII function appeared to be marginally superior to Pearson VII or Pseudo-Voigt functions. Refinement was carried out using the split-Pearson VII in the space group Pbcn (60) and terminated with a = 5.6871(6), b = 4.7846(5), c = 14.645(1) Å, V = 398.50 Å3, Z=4, Dc= 2.502 gcm−3, Rwp = 17.06, Rex = 14.48 and Χ2 = 1.39. The refined parameters are compared with those obtained from a previous single crystal X-ray determination.

Download Full-text

Rietveld Structure Refinement of the Stilbite Crystals from Deccan Traps (India) Using X-ray Powder Diffraction Data

Revista de Chimie ◽

10.37358/rc.19.7.7344 ◽

2019 ◽

Vol 70 (7) ◽

pp. 2379-2384

Author(s):

Gheorghe Branoiu ◽

Ibrahim Ramadan

Keyword(s):

Crystal Structure ◽

Rietveld Refinement ◽

Powder Diffraction ◽

Diffraction Data ◽

Structure Refinement ◽

Deccan Traps ◽

Western India ◽

Powder Diffraction Data ◽

X Ray ◽

Cell Parameters

The crystal structure of a spectacular sample of stilbite from Pune region located in the Deccan Traps (western India) has been refined using X-Ray powder diffraction data and the Rietveld method. The Rietveld refinement was carried out using the computer program Diffracplus TOPAS 4.1. The pseudo-Voigt (pV) profile function was used for the fit of the peaks. The Rietveld refinement of the analyzed sample in the space group C2/m (No.12): a=13.606 �, b=18.260 �, c=11.253 �, b=127.432�, Z=8, confirm the basic stilbite structure. The chemical composition of the stilbite crystals from Pune region (India) was determined by EDX analysis. The paper presents a new set of the unit cell parameters and fractional coordinates that define the stilbite crystal structure. The quality of the sample analyzed was pristine, the sample being collected from an association of apophyllite-stilbite crystals of centimetric dimensions.

Download Full-text