利用电子能量损失谱对二氧化铀电子结构的研究

利用电子能量损失谱对二氧化铀电子结构的研究

曾荣光^1,2，张 雷²，刘柯钊²，胡 殷²，刘天伟²，田 鹤^1*，赵雅文^2*

( 1. 浙江大学电子显微镜中心，浙江 杭州 310027; 2. 中国工程物理研究院，四川 绵阳 621900)

摘  要  锕系元素因具有复杂的5f电子结构，其显示出神秘而又独特的物理、化学特性。为了加深对锕系金属、合金和化合物的特异行为的理解，对其电子结构精确表征的重要性日益凸显。电子显微技术与电子能量损失谱技术的结合在锕系元素原子结构和电子结构研究中发挥了至关重要的作用。本文采用电子能量损失谱研究二氧化铀的5f电子结构，并讨论了铀5f电子的相互作用特性。

关键词  电子能量损失谱; 锕系材料；电子结构

中图分类号：TL27   文献标识码：A     doi:10.3969/j.issn.1000-6281.2017.01.001

Study of electronic structure of actinides using electron energy loss spectroscopy

ZENG Rong-guang^1,2，ZHANG Lei²，LIU Ke-zhao²，HU Yin²，LIU Tian-wei²，TIAN He^1*，ZHAO Ya-wen^2*

(1. Center of Electron Microscope，Zhejiang University，Hangzhou Zhejiang 310027；2. China Academy of Engineering Physics，Mianyang Sichuan 621900，China)

Abstract  The actinides exhibit intriguing and uniquephysicochemical properties due to the complicated electronic structure of the 5f states. To achieve a better understanding of the distinct properties of actinide metals, alloys, and compounds, an accurate characterization for electronic structure is required. The high resolution transmission electron microscopy combined with electron energy loss spectroscopy (TEM-EELS) methods which are of great importance have been employed to investigate the local atomic and electronic structure for actinides at the sub-Angstrom scale. In this work, we employ EELS to study the 5f electron structure of UO₂ and the 5f electron interaction.

Keywords  EELS；actinides；electronicstructure

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