Antistructural defects in lead chalcogenides

It is shown by means of emission Moessbauer spectroscopy on 119Sb(119mSn) and 119mTe(119mSn) isotopes that the charge state of the 119mSn antistructural defect arising in the anion sublattice after radioactive conversion of 119Sb and 119mTe does not depend on the Fermi level position. In contrast, the 119mSn centre in the cation sublattice of PbS and PbSe acts like an electrically active substitutional impurity: in n-type samples the spectrum corresponds to the neutral state of a donor centre (119mSn2+), while in p-type samples it corresponds to the twice ionized state of this centre (119mSn4+). In the case of PbTe the tin centres in the cation sublattice are electrically neutral and are stabilized as 119mSn2+ ions. The localization of antimony impurity atoms in the PbS, PbSe and PbTe lattices depends on the conductivity type of the material: in n-type samples the antimony is mainly localized in the anion sublattice, while in p-type samples it is mainly in the cation sublattice