A raman spectroscopic study of Al-Si ordering in synthetic magnesium cordierite |
| |
Authors: | Paul McMillan Andrew Putnis Michael A Carpenter |
| |
Institution: | 1. Department of Chemistry, Arizona State University, 85287, Tempe, Arizona, USA 2. Department of Earth Sciences, University of Cambridge, Downing Street, CB2 3EQ, Cambridge, England
|
| |
Abstract: | A number of previous investigations have examined the ordering behavior of magnesium cordierite using X-ray diffraction, transmission electron microscopy, infrared spectroscopy and solution calorimetry. In the present investigation, one series of samples from the above studies has been examined by Raman spectroscopy. Systematic modifications in the spectra with annealing time at 1,200° C are consistent with a continuous ordering of the average Al/Si distribution from 4 h to at least 64 h, and which may begin earlier. Spectral changes are first definitely observed when the ordered domains are around 100 Å across, suggesting that Raman spectroscopy is sensitive to this distance scale. The spectra of samples annealed at 1,200° C are compared with samples annealed at 1,400°; C where ordering proceeds much faster, and the possible use of Raman spectroscopy in characterization of Al/Si order in cordierite is discussed. Finally, the Raman spectrum of Mg2Al4Si5O18 with a stuffed β-quartz structure has been obtained. Comparison of its spectrum with that of cordierite glass suggests similar structures for both, which seem different to that of disordered cordierite. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|