Evaluation via multivariate techniques of scale factor variability in the rietveld method applied to quantitative phase analysis with X ray powder diffraction



Título del documento: Evaluation via multivariate techniques of scale factor variability in the rietveld method applied to quantitative phase analysis with X ray powder diffraction
Revue: Materials research
Base de datos: PERIÓDICA
Número de sistema: 000312921
ISSN: 1516-1439
Autores: 1

2
Instituciones: 1Universidade Federal do Para, Departamento de Estatistica, Belem, Para. Brasil
2Pontificia Universidade Catolica do Rio de Janeiro, Rio de Janeiro. Brasil
Año:
Periodo: Oct-Dic
Volumen: 9
Número: 4
Paginación: 369-374
País: Brasil
Idioma: Inglés
Tipo de documento: Artículo
Enfoque: Analítico
Resumen en inglés The present work uses multivariate statistical analysis as a form of establishing the main sources of error in the Quantitative Phase Analysis (QPA) using the Rietveld method. The quantitative determination of crystalline phases using x ray powder diffraction is a complex measurement process whose results are influenced by several factors. Ternary mixtures of Al2O3, MgO and NiO were prepared under controlled conditions and the diffractions were obtained using the Bragg-Brentano geometric arrangement. It was possible to establish four sources of critical variations: the experimental absorption and the scale factor of NiO, which is the phase with the greatest linear absorption coefficient of the ternary mixture; the instrumental characteristics represented by mechanical errors of the goniometer and sample displacement; the other two phases (Al2O3 and MgO); and the temperature and relative humidity of the air in the laboratory. The error sources excessively impair the QPA with the Rietveld method. Therefore it becomes necessary to control them during the measurement procedure
Disciplinas: Ingeniería,
Física y astronomía
Palabras clave: Ingeniería de materiales,
Termodinámica y física estadística,
Análisis multivariado,
Método de Rietveld,
Análisis cuantitativo de fases
Keyword: Engineering,
Physics and astronomy,
Materials engineering,
Thermodynamics and statistical physics,
Multivariate analysis,
Rietveld method,
Quantitative phase analysis
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