On the morphology of BaMoO₄ crystals: A theoretical and experimental approach

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• 作者：Marisa C. Oliveira ; Lourdes Gracia ; Iç ; amira C. Nogueira ; Maria Fernanda C. Gurgel ; Jose Manuel R. Mercury ; Elson Longo and Juan André ; s
• 刊名：Crystal Research and Technology
• 出版年：2016
• 出版时间：October 2016
• 年：2016
• 卷：51
• 期：10
• 页码：634-644
• 全文大小：1834K
• ISSN：1521-4079

文摘

BaMoO₄ crystals were obtained by a co-precipitation method, and their structures were characterized by X-ray diffraction and Rietveld refinement techniques. Field emission scanning electron microscopy was utilized to investigate the morphology of the as-synthesized aggregates.- Through systematic first principle calculations within the density functional theory method at the B3LYP level, we investigated the structure; the surface stability of the (001), (101), (110), (100), (111), and (112) surfaces; and the morphological transformations of BaMoO₄. The relative surfaces energies were further varied to predict a complete map of the available morphologies through a Wulff construction approach. This revealed that the obtained experimental and theoretical morphologies coincided when the surface energy values of the (001) surface decreased while those of the (100) and (101) facets increased simultaneously. Analysis of the surface structures showed that the electronic properties were associated with the presence of undercoordinated [BaO_x] (x = 4, 5, and 6) and [MoO_y] (y = 3) clusters. The presented results provide a comprehensive catalog of the morphologies most likely to be present under realistic conditions, and will serve as a starting point for future studies on the surface chemistry of BaMoO₄ crystals.