Re: Variable Step Size reference
I don't think that varying the step size is particularly useful. The FWHM usually increases with angle for sure, but so does the number of peaks per degree, so you want the finest step to stand a chance of seeing any subtleties in the profile due to overlapping peaks. I think it's more useful to increase the counting time to counteract the reduction in scattering power with angle. Andy On 04/04/2022 11:28, francois Goutenoire wrote: Dear Rietveld users, I am currently looking for a reference for the strategy of collecting XRD data on lab diffractometer. With the help of new diffractometers we can collect the data in the VCT (Variable Counting Time). This last method has been studied by IC Madsen and RJ Hill (1994). Now we can also collect the data with different step size for a long two theta range (example : from 5 to 150 two theta) with some different steps size depending of the FWHM evolution (example 0.013 / 0.026 and 0.039). After the data can be easily modified to get the 0.013 step (HighScorePlus). Is there any good paper about this VCT -VSS (Variable Step Size) methodology ? Best wishes, Francois -- * Pr. Francois GOUTENOIRE e-mail:francois.gouteno...@univ-lemans.fr Tel: 02.43.83.33.54 FAX: 02.43.83.35.06 Institut des Molécules et des Matériaux du Mans IMMM - UMR CNRS 6283 Elaboration et Caracterisation des Composés Cristalisés (E3C) Université du Maine - Avenue Olivier Messiaen F-72085 Le Mans Cedex 9 FRANCE * Formation Rietveld CNRS https://cnrsformation.cnrs.fr/diffraction-des-rayons-x-sur-materiaux-polycristallins?axe=135 Formation EDX CNRS https://cnrsformation.cnrs.fr/fluorescence-x-edx?axe=135 Formation SAXS et Réflectivités pour couches minces et matériaux nanostructurés. https://cnrsformation.cnrs.fr/caracterisation-des-materiaux-nanostructures-par-diffusion-des-rayons-x?axe=135 Bibliographie https://scholar.google.fr/citations?hl=fr=qC-lmN4J_op=list_works=1=title https://orcid.org/-0001-5339-3002 ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body text The Rietveld_L list archive is onhttp://www.mail-archive.com/rietveld_l@ill.fr/ ++ ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++
RE: Variable Step Size reference
Dear Francois, I know this one: Routine ab initio structure determination of chlorothiazide by X-ray powder diffraction using optimised data collection and analysis strategies Kenneth Shankland,* William I. F. David and Devinderjit S. Sivia J. Mater. Chem., 1997, 7(3), 569–572 https://doi.org/10.1039/A606998C Jan Od: rietveld_l-requ...@ill.fr za uživatele francois Goutenoire Odesláno: Monday, April 4, 2022 11:28 AM Komu: Rietveld List (rietveld_l@ill.fr) Předmět: Variable Step Size reference Dear Rietveld users, I am currently looking for a reference for the strategy of collecting XRD data on lab diffractometer. With the help of new diffractometers we can collect the data in the VCT (Variable Counting Time). This last method has been studied by IC Madsen and RJ Hill (1994). Now we can also collect the data with different step size for a long two theta range (example : from 5 to 150 two theta) with some different steps size depending of the FWHM evolution (example 0.013 / 0.026 and 0.039). After the data can be easily modified to get the 0.013 step (HighScorePlus). Is there any good paper about this VCT -VSS (Variable Step Size) methodology ? Best wishes, Francois -- * Pr. Francois GOUTENOIRE e-mail: francois.gouteno...@univ-lemans.fr <mailto:francois.gouteno...@univ-lemans.fr> Tel: 02.43.83.33.54 FAX: 02.43.83.35.06 Institut des Molécules et des Matériaux du Mans IMMM - UMR CNRS 6283 Elaboration et Caracterisation des Composés Cristalisés (E3C) Université du Maine - Avenue Olivier Messiaen F-72085 Le Mans Cedex 9 FRANCE * Formation Rietveld CNRS https://cnrsformation.cnrs.fr/diffraction-des-rayons-x-sur-materiaux-polycristallins?axe=135 Formation EDX CNRS https://cnrsformation.cnrs.fr/fluorescence-x-edx?axe=135 Formation SAXS et Réflectivités pour couches minces et matériaux nanostructurés. https://cnrsformation.cnrs.fr/caracterisation-des-materiaux-nanostructures-par-diffusion-des-rayons-x?axe=135 Bibliographie https://scholar.google.fr/citations?hl=fr <https://scholar.google.fr/citations?hl=fr=qC-lmN4J_op=list_works=1=title> =qC-lmN4J_op=list_works=1=title https://orcid.org/-0001-5339-3002 ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++
Variable Step Size reference
Dear Rietveld users, I am currently looking for a reference for the strategy of collecting XRD data on lab diffractometer. With the help of new diffractometers we can collect the data in the VCT (Variable Counting Time). This last method has been studied by IC Madsen and RJ Hill (1994). Now we can also collect the data with different step size for a long two theta range (example : from 5 to 150 two theta) with some different steps size depending of the FWHM evolution (example 0.013 / 0.026 and 0.039). After the data can be easily modified to get the 0.013 step (HighScorePlus). Is there any good paper about this VCT -VSS (Variable Step Size) methodology ? Best wishes, Francois -- * Pr. Francois GOUTENOIRE e-mail:francois.gouteno...@univ-lemans.fr Tel: 02.43.83.33.54 FAX: 02.43.83.35.06 Institut des Molécules et des Matériaux du Mans IMMM - UMR CNRS 6283 Elaboration et Caracterisation des Composés Cristalisés (E3C) Université du Maine - Avenue Olivier Messiaen F-72085 Le Mans Cedex 9 FRANCE * Formation Rietveld CNRS https://cnrsformation.cnrs.fr/diffraction-des-rayons-x-sur-materiaux-polycristallins?axe=135 Formation EDX CNRS https://cnrsformation.cnrs.fr/fluorescence-x-edx?axe=135 Formation SAXS et Réflectivités pour couches minces et matériaux nanostructurés. https://cnrsformation.cnrs.fr/caracterisation-des-materiaux-nanostructures-par-diffusion-des-rayons-x?axe=135 Bibliographie https://scholar.google.fr/citations?hl=fr=qC-lmN4J_op=list_works=1=title https://orcid.org/-0001-5339-3002 ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++
