The Three-Body Correlation Function in Amorphous Silicon Probed by X-Ray Absorption Spectroscopy

In this paper we present structural results on the three-body correlation function in amorphous silicon as determined by the X-ray absorption spectroscopy (XAS). It is shown, for the first time, that the XAS can provide quantitative information beyond the pair correlation. The theoretical analysis is performed using an original formulation of the multiple-scattering theory of the XAS in terms of the n -body distribution functions. These results are compared with recent computer simulations of continuous random network models.