A Crystallographic Contribution to the Mechanism of a Mechanically Induced Solid State Reaction

doi:10.1006/jssc.1996.0113

Journal of Solid State Chemistry

Volume 122, Issue 2, March 1996, Pages 273-280

https://doi.org/10.1006/jssc.1996.0113 Get rights and content

Abstract

Using X-ray diffraction analysis and Raman spectroscopy techniques, a mechanically induced double displacement reaction has been used to investigate the chemical mechanism by which mechanical alloying occurs. The specific reaction studied was the reduction of cupric oxide by iron. From Rietveld analysis of milled powders, isotropic atomic displacement parameters are refined and the lattice strain involved in displacing oxygen in the CuO lattice is then calculated. In addition, anisotropic atomic displacement parameters are refined, providing information regarding the reaction pathway. Raman spectroscopy is used to differentiate between thermal motion and static displacement of oxygen atoms in the CuO lattice. Using this information, the mechanism of a mechanically induced solid state reaction is described.

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The peaks at 147 and 798 cm−1 can be assigned to Raman scattering from phonons of symmetry Г15− [98], while the peak appearing at 636 cm−1 is attributed to infrared-allowed mode [99]. The peak at 294 cm−1 corresponds to the Ag mode of CuO (where Ag mode is the symmetric O translational mode in the y direction along the crystallographic b axis) [100]. The Raman spectrum confirms that the laser-generated Cu/Cu2O films possess a good crystalline phase compared to pristine Cu.
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Regular ArticleA Crystallographic Contribution to the Mechanism of a Mechanically Induced Solid State Reaction

Abstract

Regular Article
A Crystallographic Contribution to the Mechanism of a Mechanically Induced Solid State Reaction