The Development of Three-Dimensional Differential Pair Distribution Function Method for Shanghai Synchrotron Radiation Facility

[Backgound] In recent years, the three-dimensional differential atomic pair distribution function (3D-ΔPDF) method has received significant attention from researchers in synthetic chemistry, condense matter physics, and material science. Benefited from the high brightness and intensity of next-generation synchrotron radiation sources, 3D-ΔPDF can provide unprecented insight into the local structure of materials at the atomic level. [Purpose] This study aims to promote the implementation of the three-dimensional differential atomic pair distribution function method at different energy beamlines of the Shanghai Synchrotron Radiation Facility (SSRF) and to verify its effectiveness and reproducibility in the local structure analysis of single-crystal materials. [Methods] Single crystal experiments were conducted on PbTe and Zr0.91Y0.09O29 (YSZ) samples at the BL12SW beamline of SSRF, resulting in three-dimensional total scattering datasets. The 3D-ΔPDF method was employed to remove the Bragg diffraction signals and directly analyze the correlation functions in three-dimensional space. [Results] The results demonstrate that under low-temperature conditions, the reduction of thermal vibration-induced diffuse scattering significantly enhances the resolution of 3D-ΔPDF experiments. This approach reveals the presence of local symmetry breaking in the PbTe system, providing critical insights into the structural origins of its exceptional thermoelectric properties. Additionally, the 5858E detector exhibits superior signal detection efficiency under the same beam conditions, improving real-space resolution and capturing finer details of the 3D-ΔPDF analysis. [Conclusions] This work validates the accuracy and reproducibility of the 3D-ΔPDF method, demonstrating its capability to precisely identify and analyze local structural changes in materials. It is expected to become an important characterization method for advancing the understanding of local structural information in materials science.