Abstract
Two-electron exchange between neutral and doubly ionized negative-U tin centers in PbS and PbSe has been studied by Mossbauer emission spectroscopy. The activation energy for this process in PbS is 0.11(2) eV, which is comparable to the depth of tin levels in the band gap of PbS, whereas the activation energy for this process in PbSe, 0.05(1) eV, is comparable to the correlation energy of negative-U donor tin centers in PbSe. The exchange occurs through simultaneous transfer of two electrons and involves valence band states.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have