Local Atomic Structure of Complex Oxides

摘要：巨磁阻（CMR）锰酸盐和高温超导铜酸盐等具有不同于普通晶体结构的原子级和纳米级局部结构，且这些局部结构比普通结构更直接地影响其电子性能。该项目的目标是利用脉冲中子散射、同步加速器x射线散射和建模来确定复杂电子氧化物的局部结构。我们使用原子对密度函数（PDF）方法对包括漫射散射在内的总散射数据进行分析，直接确定了原子间的距离。该项目所获得的知识将为快速发展的高敏感氧化物技术提供科学依据，并为提高其性能提供方法。该项目还与洛斯阿拉莫斯中子科学中心的脉冲中子粉末衍射光束线（NPD）的升级工作有关，该中心由美国国家科学基金会和美国能源部支持。

0102565Egami Complex electronic oxides that show remarkable properties, such as the colossal magnetoresistive (CMR) manganites and the high-temperature superconductive cuprates, have atomic and nano-scale local structures that are distinct from the average crystal structure, and these local structures more directly influence their electronic properties than the average structure does. The goal of this project is to determine the local structure of complex electronic oxides using pulsed neutron scattering, synchrotron x-ray scattering and modeling. We directly determine the distances between atoms using the method of the atomic pair-density function (PDF) analysis of the total scattering data including diffuse scattering. %%%The knowledge obtained by this project would form a scientific basis for the rapidly developing technology of highly sensitive oxides, and would suggest ways of improving their performance. This project is also related to the effort to upgrade a pulsed neutron powder diffraction beamline, NPD, at the Los Alamos Neutron Science Center, supported by the NSF and DOE.