Cu 2p-1s x-ray emission spectroscopy of mineral tetrahedrite Cu12Sb4S13

Abstract The electronic structure of mineral tetrahedrite Cu 12 Sb 4 S 13 showing a metal-semiconductor transition (MST) at T MST = 85 K has been investigated by means of Cu 1s x-ray absorption spectroscopy with the partial fluorescence yield mode (PFY-XAS) and Cu 2p-1s x-ray emission spectroscopy (XES). Remarkable changes are detected in both the PFY-XAS and XES spectra on cooling across T MST . The changes in the spectra indicate that the unoccupied Cu 3d and 4p densities of states (DOS) shift away from the Fermi energy (E F ). We conclude that the MST of Cu 12 Sb 4 S 13 is associated with the decrease of the Cu 3d DOS at E F .