Abstract
The effect of thermal disorders on the anharmonic extended X-ray absorption fine structure (EXAFS) parameters of crystalline silver (Ag) has been investigated in the wavenumber and temperature dependencies. The calculation model is developed based on the correlated Debye model using the many-body perturbation (MBP) theory and anharmonic effective (AE) potential. The anharmonicity of the EXAFS signal is caused by the effect of thermal disorders and results from phonon-phonon interactions, with each thermal vibration being quantized and treated as a phonon. The considered EXAFS parameters include the first four cumulants, amplitude reduction, and phase shift of the anharmonic EXAFS signal. The obtained expressions are explicit and can satisfy all their temperature-dependent properties. The numerical results of Ag agree well with those obtained from the experimental data and other calculation models in the temperature range from 0 to 1000 K and the wavenumber range from 0 to 14.14 Å. The obtained results indicate the effectiveness of the present model in investigating the anharmonic EXAFS parameters of Ag from above zero point to near the melting point.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call