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在相对温和的水热体系里合成出纳米品Sr-Cr水合石榴石,采用XRD、IR和XPS光谱图对产物进行了表征.结果表明,高溶解性的初始物和高浓度的矿化剂大大降低其晶化温度,并提高其结晶度.随温度升高,出现Sr十二面体最近邻的OH-断裂与分解过程,在空气或氧气中,还出现了Cr(Ⅲ)到Cr(Ⅳ)氧化过程.骨架离子Cr(Ⅲ)的价态变化直接决定着水合石榴石的分解过程及其产物的结构类型,低温磁化率测量表明Sr3Cr2(OH)12是顺磁性的;在该结构中出现了轨道角动量的完全猝灭.该结构中存在较高对称性的Cr-OH八面体.
Nanostructured Sr-Cr hydrated garnets were synthesized in a relatively mild hydrothermal system. The products were characterized by XRD, IR and XPS spectra. The results show that the high solubility of the initial and high concentrations of mineralizer greatly reduce the crystallization temperature and increase its crystallinity. With the increase of temperature, OH-fracture and decomposition of the nearest neighbor of Sr dodecahedron occur, and oxidation of Cr (Ⅲ) to Cr (Ⅳ) also occurs in air or oxygen. Variations in the valence of the framework ions Cr (III) directly determine the decomposition process of the hydrated garnet and the structure of the product. The low temperature magnetic susceptibility measurements show that Sr3Cr2 (OH) 12 is paramagnetic. The orbital angular momentum Complete quenching. There is a high symmetry Cr-OH octahedron in this structure.