Homogeneous and Heterogeneous Mechanochemical Reactions in Spinels Studied by Mössbauer Spectroscopy and NMR

由于它们能够探测特定原子核的局部环境，固态核磁共振和穆斯堡尔谱学将提供对尖晶石氧化物中远离平衡的机械力化学过程的详细洞察。关于局部结构无序的定量信息(非平衡阳离子分布、倾斜的自旋排列、最近邻构型的改变、多面体几何形状的变形等)。以及离子在机械力化学法制备的纳米复合氧化物中的扩散现象和动力学。阐明机械合成纳米粒子核壳结构形成的微观机制，拓展对各种化学成分相关纳米结构中粒子核壳内非平衡离子分布和倾斜自旋排列的认识，将具有重要意义。除了核光谱技术提供的关于短程结构的信息外，还将在宏观范围内调查机械化学法制备的氧化物的行为和性质，以确定其纳米结构和磁性之间的相互作用。

Due to their capabilities to probe the local environment of a particular nucleus, solid-state nuclear magnetic resonance and Mössbauer spectroscopy will provide detailed insight into the far-from-equilibrium mechanochemical processes in spinel oxides. Quantitative information on the local structural disorder (a nonequilibrium cation distribution, a canted spin arrangement, an alteration of the nearest-neighbor configuration, a deformation of the polyhedron geometry, etc.) as well as on the diffusion phenomena and dynamics of ions in nanocrystalline complex oxides prepared by mechanochemical routes will be obtained. It will be of major importance to clarify the microscopic mechanism leading to the formation of the core–shell configuration in mechanosynthesized nanoparticles and to expand the understanding of both nonequilibrium ionic distribution and canted spin arrangement within the particle core and shell in the series of related nanostructures of various chemical compositions. Information on the short-range structure, provided by the nuclear spectroscopic techniques, will be complemented by the investigation of the behavior and properties of mechanochemically prepared oxides on a macroscopic scale with the aim to establish the interplay of their nanostructure and magnetism.