抄録
<jats:title>Abstract</jats:title><jats:p>Low-temperature FTIR spectroscopy was used to characterize the v(OH) region of kaolin-group minerals including well ordered to poorly ordered kaolins from Georgia, Brazil, and England, along with samples of discrete dickite and nacrite. Low-temperature FTIR spectra were useful in resolving dickite- and nacrite-like features present in the spectra of kaolins when cooled to <30 K. These features were not resolved at room temperature and only partially resolved at liquid N<jats:sub>2</jats:sub> temperature (77 K). The room-temperature and low-temperature positions of the <jats:italic>ν</jats:italic>(OH) bands of kaolinite, dickite, and nacrite were linearly correlated with the interatomic OH⋯O distances and this relationship served as the basis for polytype/disorder identification. Dickite or dickite-like disorder was found in high Hinckley-Index kaolinite from Keokuk, Iowa, and from Cornwall, England. Dickite- and nacrite-like features were observed in both high- and low-Hinckley-index kaolinite and the amounts of these stacking sequences generally increased with decreasing Hinckley Index.</jats:p>
収録刊行物
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- Clays and Clay Minerals
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Clays and Clay Minerals 56 (4), 470-485, 2008-08
Cambridge University Press (CUP)