Recently there has been a growing interest in the electride phase of sp-bonded materials at extremely high pressures >Mbar (see attached paper for example). This phase is characterized by a matrix of positive ions and interstitial electron blobs. I am wondering how XAFS signal would change when these electron blobs are present. The x-ray diffraction probably won't detect them directly. But XAFS might be able to show their existence if they behave like additional scattering centers.