CETMIC   05378
CENTRO DE TECNOLOGIA DE RECURSOS MINERALES Y CERAMICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Experimental and theoretical characterization of kaolinite by DFT, XANES ab initio simulations, Al K XANES and Si K XANES/EXAFS
Autor/es:
N. M. RENDTORFF; M. MIZRAHI; D. RICHARD; L. ANDRINI
Lugar:
Campinas
Reunión:
Encuentro; 29th Annual Users Meeting; 2019
Resumen:
Kaolinite(Al2O3·2SiO2·4H2O)is classified as a 1:1 dioctahedral phyllosilicate and it is the maincomponent of the kaolin group of minerals. The importance ofkaolinitic clays in the development of modern ceramic science canbest be appreciated by considering its widespread influence onceramic, material science, and mineralogy. These clays have beenwidely used in different technological applications for thousands ofyears [1]. Itstechnological importance requires an exhaustive study of itsmorphological nature as an electronic structure. In a recent paper[2] a detailedfirst principles study of the bulk structure of kaolinite wascarried out, and thepredictions solve previous controversies around kaolinite bulkstructure. Inthis work we extend the theoretical aspects, to introduce thestructures generated by DFT-calculus in the FEFF, FDMNES and SPR-KKRprograms to simulate the absorption spectra in the K edge of the Aland Si, correlating these results with the experimental data obtainedin the SXS-beamline (LNLS, Campinas, SP, Brazil). In addition, Si KEXAFS spectra were obtained for kaolinites with different degrees ofcrystallinity and distortions. This allows to make adjustments of theEXAFS signal and its corresponding Fourier transform, and comparewith the models obtained by DFT. In this meeting we present theadvances of this research. Workin progress.[1]L. Andrini, M.R. Gauna, M.S. Conconi, G. Suarez, F.G. Requejo, E.F.Aglietti and N.M. Rendtorff, Appl.Clay Sci.,124,39 (2016).[2]D. Richard and N.M. Rendtorff, Appl.Clay Sci.,169,67 (2019).Acknowledgements:This work has been supported by LNLS under Proposals SXS- 20180272and SXS- 20190124. The authors would like tothank CETMIC, INIFTA, Facultad de Ciencias Exactas, UniversidadNacional de La Plata, CONICET.p { margin-bottom: 0.1in; direction: ltr; color: #000000; line-height: 120%; orphans: 2; widows: 2; background: transparent }p.western { font-family: "Liberation Serif", "Times New Roman", serif; font-size: 12pt; so-language: en-US }p.cjk { font-family: "Noto Sans CJK SC Regular", "Times New Roman"; font-size: 12pt; so-language: zh-CN }p.ctl { font-family: "Lohit Devanagari"; font-size: 12pt; so-language: hi-IN }