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Mg[Al.sub.2][O.sub.4] spinel was synthesized by a novel route method of sol-gel technique. Spinel powders were sintered at various temperatures to investigate the phase contents and crystallinity. The characterization of the samples was carried out by using various techniques. The formation of the spinel phase was inferred by differential thermal analyzer, while crystalline and structural properties were studied by X-ray diffraction, Fourier transform infrared spectroscopy and magic angle spinning nuclear magnetic resonance (MAS-NMR). These studies infer the formation of spinel phase at much lower temperature (around 375[degrees]C) and order-disorder transition in the spinel around 700[degrees]C. The studies also indicate the formation of the spinel with better crystallinity. The inversion parameter was also calculated using MAS-NMR and its value is found to be approximately 0.30 for a sample sintered around 1000[degrees]C. PACS Nos.: 81.20.Fw. Nous synthetisons le spinelle Mg[Al.sub.2][O.sub.4] a l'aide d'une nouvelle technique sol-gel. Les poudres de spinelle sont traitees par frittage a differentes temperatures pour etudier les contenus de phase et la cristallinite. Differentes techniques permettent de caracteriser les echantillons. La formation de la phase spinelle est deduite par analyse thermale differentielle, alors que les proprietes cristallines et structurelles sont etudiees par diffraction, par spectroscopie infrarouge fi transformee de Fourrier et par NMR a rotation a l'angle magique (MAS-NMR). Ces etudes concluent a la formation de la phase spinelle a beaucoup plus basse temperature (autour de 375[degrees]C) et a une transition ordre-desordre dans le spinelle autour de 700[degrees]C. Ces memes etudes indiquent aussi la formation du spinelle avec une meilleure cristallinite. Nous calculons egalement le parametre d'inversion en utilisant MAS-NMR et trouvons sa valeur aux environs de 0.30 pour un echantillon soumis au frittage autour de 1000[degrees]C. [Traduit par la Redaction], Introduction Spinel is a class of material that has technological applications in electrical and electronic devices and in heavy industry as refractories. In particular, the spinel Mg[Al.sub.2][O.sub.4] has a variety [...]

MgAl2O4 spinel was synthesized by a novel route method of sol-gel technique. Spinel powders were sintered at various temperatures to investigate the phase contents and crystallinity. The characterization of the samples was carried out by using various techniques. The formation of the spinel phase was inferred by differential thermal analyzer, while crystalline and structural properties were studied by X-ray diffraction, Fourier transform infrared spectroscopy and magic angle spinning nuclear magnetic resonance (MAS-NMR). These studies infer the formation of spinel phase at much lower temperature (around 375 °C) and order-disorder transition in the spinel around 700 °C. The studies also indicate the formation of the spinel with better crystallinity. The inversion parameter was also calculated using MAS-NMR and its value is found to be approximately 0.30 for a sample sintered around 1000 °C. [ABSTRACT FROM AUTHOR]