Application of combined multivariate techniques for the description of time-resolved powder X-ray diffraction data

0473532 - ÚTAM 2018 RIV GB eng J - Journal Article
Taris, A. - Grosso, M. - Brundu, M. - Guida, V. - Viani, Alberto
Application of combined multivariate techniques for the description of time-resolved powder X-ray diffraction data.
Journal of Applied Crystallography. Roč. 50, č. 2 (2017), s. 451-461. ISSN 0021-8898. E-ISSN 1600-5767
R&D Projects: GA MŠMT(CZ) LO1219
Keywords : in situ X-ray powder diffraction * amorphous content * chemically bonded ceramics * statistical total correlation spectroscopy * multivariate curve resolution
OECD category: Materials engineering
Impact factor: 3.422, year: 2017
http://journals.iucr.org/j/issues/2017/02/00/ap5006/index.html

In this work, multivariate statistical techniques are employed to determine patterns and conversion curves from time-resolved X-ray powder diffraction data. For these purposes, time-window statistical total correlation spectroscopy is introduced for the pattern matching of the crystalline phase and is shown to be effective even in the case of overlapping peaks. When combined with evolving factor analysis and multivariate curve resolution–alternating least squares, this technique allows a definite estimation of patterns and conversion curves. The procedure is applied to in situ synchrotron powder diffraction patterns to monitor the setting reaction of magnesium potassium phosphate ceramic (MKP) from magnesia (MgO) and potassium dihydrogen phosphate. It is shown that the phases involved in the reaction are clearly distinguished and their evolution is correctly described. The conversion curves estimated with the proposed procedure are compared with the ones determined with the peak integration method, leading to an excellent agreement (Pearson’s correlation coefficient equal to 0.9995 and 0.9998 for MgO and MKP, respectively). The approach also allows for the detection and description of the evolution of amorphous phases that cannot be described through conventional analysis of powder diffraction data.
Permanent Link: http://hdl.handle.net/11104/0270719