Hubbard energy of two-electron tin centers in PbS1-zTez solid solutions

It is shown by Mossbauer spectroscopy of the isotope Sn-119 that an isovale nt tin impurity in PbS1-zTez solid solutions is a two-electron donor with a negative correlation energy, where the energy levels associated with tin c enters are situated against the background of the valence band continuum. T he Hubbard energy U is estimated for impurity tin atoms in PbS1-zTez (\U\> 0.2 eV), which is found to be substantially higher than for analogous tin c enters in PbS1-zSez solid solutions (\U\=0.058 eV). (C) 1999 American Insti tute of Physics. [S1063-7826(99)00607-9].