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Wavelet denoising of powder diffraction patterns

Published online by Cambridge University Press:  10 January 2013

Ľubomír Smrčok*
Affiliation:
Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-842 36 Bratislava, Slovak Republic
Marián Ďurík
Affiliation:
Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-842 36 Bratislava, Slovak Republic
Vladimír Jorík
Affiliation:
Department of Inorganic Chemistry, Slovak Technical University, SK-812 37 Bratislava, Slovak Republic
*
a)Corresponding author, electronic mail: [email protected]

Abstract

Four powder diffraction patterns taken under different experimental conditions were denoised by a new method, i.e., thresholding of wavelet coefficients. The patterns were transformed by discrete wavelet transform applying Coiflet4 wavelet function. WLS refinements of peaks’ positions, FWHM, and intensity showed that wavelet denoising, in contrast to previously used polynomial smoothing, did not shift the maxima and preserved peak and integrated intensities. This method may therefore represent an useful alternative to polynomial filters or filters based on Fourier transform.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1999

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