Programme

P.79 -- Posters, VCTP-51

Date: Thursday, 6 August 2026

Time: 09:30 - 10:30

Temperature-dependent EXAFS parameters of wurtzite CdSe derived from a classical correlated Einstein model

Nguyen Thi Minh Thuy (1,2), Tong Sy Tien (1,*), Nguyen Huy Thao (2), Le Viet Hoang (3), Nguyen Cong Toan (3), Nguyen Nhu Xuan

(1) Faculty of Fundamental Sciences, University of Fire Prevention & Fighting, Hanoi 12010, Vietnam (2) Department of Physics, Hanoi Pedagogical University 2, Phu Tho 15910, Vietnam (3) Department of Physics, Hanoi University of Science, Hanoi 11417, Vietnam (4) Le Quy Don Technical University, Hanoi 11307, Vietnam

The temperature-dependent extended X-ray absorption fine structure (EXAFS) parameters of wurtzite CdSe are investigated using a correlated Einstein model combined with an anharmonic effective potential based on a classical statistical approach. The effective potential is constructed to incorporate the ionic nature of the Cd–Se interaction and the local coordination geometry of the wurtzite structure. Analytical expressions for the effective potential, correlated Einstein frequency, Einstein temperature, and the first four EXAFS cumulants are obtained as functions of temperature. Numerical results reveal the effects of temperature on the local pair distribution and anharmonicity of the Cd–Se bond. Comparison with available experimental EXAFS data over the temperature range 18–300 K is used to evaluate the applicability of the present model. The present approach provides an efficient framework for describing local anharmonic vibrations and EXAFS cumulants in ionic wurtzite crystals.

Presenter: Tong Sy Tien