Mossbauer emission spectroscopy on the isotope Te-119m(Sn-119m) is used to
identify tin impurity centers in PbTe and PbS lattices. Using the emission
variant of Mossbauer spectroscopy makes it possible to stabilize the tin im
purity atoms in the anion sublattice, i.e., to obtain antistructural defect
s. The charge state of the tin impurity atoms displaced from the anion subl
attice is found to depend on the position of the Fermi level. (C) 1999 Amer
ican Institute of Physics. [S1063-7826(99)00207-0].