Eur. Phys. J. B (2017) 90: 256
https://doi.org/10.1140/epjb/e2017-80383-1

Regular Article

Advances in theoretical and experimental XAFS studies of thermodynamic properties, anharmonic effects and structural determination of fcc crystals

¹ Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang, Viet Nam
² Institute of Geological Sciences (IGS), Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Cau Giay, Ha Noi, Viet Nam
³ Graduate University of Science and Technology, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Cau Giay, Ha Noi, Viet Nam
⁴ Department of Physics, Tan Trao University, Km 6, Trung Mon, Yen Son, Tuyen Quang, Viet Nam
⁵ Cam pha School, Quang Ninh Education & Training Department, Nguyen Van Cu, Ha Long, Quang Ninh, Viet Nam
⁶ Department of Basic Sciences, University of Fighting & Prevention, 243 Khuat Duy Tien, Thanh Xuan, Ha Noi, Viet Nam

^a e-mail: hungnv@vnu.edu.vn

Received: 28 June 2017
Received in final form: 8 October 2017
Published online: 18 December 2017

Abstract

Thermodynamic properties, anharmonic effects and structural determination of fcc crystals have been studied based on the theoretical and experimental Debye–Waller factors presented in terms of cumulant expansion up to the third order, thermal expansion coefficient, X-ray absorption fine structure (XAFS) spectra and their Fourier transform magnitudes. The advances in these studies are performed by the further development of the anharmonic correlated Einstein model primary only for approximating three first XAFS cumulants into the method using that all the considered theoretical and experimental XAFS parameters have been provided based on only the calculated and measured second cumulants. The obtained cumulants describe the anharmonic effects in XAFS contributing to the accurate structural determination. Numerical results for Cu are found to be in good agreement with the experimental values extracted by using the present advanced method and with those obtained by the other measurements.