Mechanochemistry of Oxide and Fluoride Nonequilibrium Phases: Mechanosynthesis, Solid State Kinetics and Spectroscopic Properties

氧化物和氟化物非平衡相的力化学：力合成、固态动力学和光谱性质

• 批准号: 142911196
• 负责人: Professor Dr. Paul Heitjans
• 金额: --
• 依托单位: Institut für Physikalische Chemie und Elektrochemie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/142911196?language=en
• 关键词: Mechanochemistry; Oxide; Fluoride; Nonequilibrium; Phases

The project deals with the directed mechanochemical synthesis and structural characterization of new crystalline oxide and fluoride non-equilibrium phases. While in the first period mainly systems crystallizing with the perovskite, olivine, garnet, fluorite, and spinel structure were investigated, in the second period, the research will be extended to more complex materials such as (i) oxides with the mullite-type structure with general composition Bi2X4O9/10 (X = Ga3+, Fe3+, Al3+, Mn3+, Mn4+), (ii) the pyroxene-type compounds, e. g., Li-containing pyroxenes LiYSi2O6 (Y = Fe3+, Al3+, Cr3+), and (iii) the Li2ZSiO4 family of oxides (Z = Fe2+, Mn2+, Co2+, Ni2+). Also other fluoride systems like BaSnF4, BaMgF4, and metastable composites based on SnF2 will be investigated. Complex problems regarding the metastable structural configurations in several systems investigated in the first period will be processed in cooperation with theoretically-oriented groups.The main focus will be given to the investigation of the mechanisms and kinetics of the formation of metastable compounds involving studies concerning their thermal stability, especially their local atomic and electronic structures. Primarily, complementary nuclear methods such as NMR- and Mössbauer spectroscopy will be used, which allow to follow the relaxation paths of the as-prepared phases to the equilibrium state and associated kinetics at the local scale. Besides the determination of the local structure of the non-equilibrium phases the investigation of the dynamic, electric and magnetic properties is the second priority of the project. The project shall contribute to an understanding of the structure-forming factors which govern the formation mechanisms of the mechanosynthesized non-equilibrium phases, in order to manipulate them in a directed way for the synthesis of new functional materials.

该项目介绍了新的氧化晶体和氟化物非平衡阶段的定向机械化学合成和结构表征。 While in the first period mainly systems crystallizing with the perovskite, olivine, garnet, fluorite, and spinel structure were investigated, in the second period, the research will be extended to more complex materials such as (i) oxides with the mullite-type structure with general composition Bi2X4O9/10 (X = Ga3+, Fe3+, Al3+, Mn3+, Mn4+), (ii) the辉石型化合物，e。 g。，含有液的pyroxenes liysi2O6（y = fe3+，al3+，cr3+）和（iii）li2ZSIO4氧化物家族（z = fe2+，mn2+，co2+，ni2+）。还将研究其他基于SNF2的氟化物系统，例如BASNF4，BAMGF4和亚稳组成。在第一阶段研究的几个系统中的亚稳态结构配置方面的复杂问题将与理论导向的组合作处理。主要重点将放在涉及其热稳定性的研究的基质化合物的机制和动力学的投资中，尤其是其本地原子和电子结构。首先，将使用完整的核方法，例如NMR-和Mössbauer光谱法，这允许在局部规模上遵循准备相的阶段的松弛路径到平衡状态和相关的动力学。除了确定非平衡阶段的局部结构外，动态，电气和磁性的投资是项目的第二个优先级。该项目应有助于理解结构形成因子​​，这些因子控制了机制的非平衡阶段机制的形成机制，以便以一种有方向的方式来合成新功能材料。