Anharmonic effects of gold in extended X-ray absorption fine structure

The anharmonic effects of gold in extended X-ray absorption fine structure (EXAFS) have been investigated through the consideration of the first four EXAFS cumulants up to temperature 800 K within the anharmonic correlated Debye model. The interatomic potential between two intermediate atoms has been described by the second-moment approximation to the tight-binding model and its parameters were determined from first-principles calculations. Our results of the first four EXAFS cumulants and anharmonic effective potential are compared with those of experiments showing the good and reasonable agreements. We have shown in detail that the anharmonicity contributions of the thermal vibration of atoms are important to EXAFS cumulants at high temperature.