Analysis of thermal diffuse scattering intensity of scandium oxide (Sc₂O₃)

Abstract

Atoms in crystals will generate thermal diffuse scattering during thermal vibration. Thermal diffuse scattering analysis has great potential and practicality in condensed matter physics and material science research. Scandium oxide (Sc<sub>2</sub>O<sub>3</sub>) has unique physical and chemical properties, which makes it have high research and application value. X-ray diffraction experiment has been performed on Sc<sub>2</sub>O<sub>3</sub> at room temperature of 26℃.The thermal diffuse scattering intensity exhibited a clear vibrational shape. The full diffraction back-base intensity equation of Sc<sub>2</sub>O<sub>3</sub> was expanded, and the theoretical value of the thermal diffuse scattering intensity was calculated until the full diffraction back-base intensity spectrum of the 14th nearest atom (<i>r</i>=0.3816nm) was calculated. By fitting the theoretical value with the experimental value, we obtained the Inter-atomic thermal vibration correlation effect value <i>μ</i> corresponding to the nearest neighbor atom to seventh nearest neighbor atom, the distances <i>r</i> from the nearest neighbor atom to the 7th nearest neighbor atom are 0.2067, 0.2148, 0.2161, 0.2671, 0.2945, 0.3229 and 0.3265nm, respectively, corresponding Inter-atomic thermal vibration correlation effect value <i>μ </i>0.64, 0.63, 0.62, 0.61, 0.60, 0.58 and 0.57. Research has found that the intensity of thermal diffuse scattering in Sc<sub>2</sub>O<sub>3</sub> is closely related to the atomic thermal vibration, The most significant influence on the vibration shape of thermal diffuse scattering intensity is the thermal vibration correlation effect between the 7th nearest atom Sc<sub>1</sub>-Sc<sub>2</sub>. Inter-atomic thermal vibration correlation effect values<i> </i><i>μ </i>will provide important parameters for studying the mechanical and thermal properties of materials, laying the foundation for the next step of calculating specific heat and interatomic force constant they play a crucial role in the use and development of materials.