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Using Messbauer spectroscopy on 119Sn impurity atoms, it was demonstrated that in amorphous (GeTe)x(Sb2Te3) films (where x = 0.5, 1, 2, 3) tin atoms replace atoms of tetravalent germanium, which forms a tetrahedral system of chemical bonds with atoms in its local environment. In crystalline films, tin replaces divalent six-coordinated germanium in positions 4b of the NaCl-type crystal lattice. [ABSTRACT FROM AUTHOR]

By the method of Mössbauer spectroscopy on the isotope 119Sn, it was shown that tetravalent germanium atoms in amorphous films (GeTe)x(Sb2Te3) (where x = 0.5, 1, 2, 3) form a tetrahedral system of chemical bonds, and in their local environment there are mainly tellurium atoms. In crystalline films (GeTe)x(Sb2Te3) is divalent hexoordinated germanium at positions 4 b of the NaCl type crystal lattice. By the method of Mössbauer spectroscopy on 121Sb and 125Te atoms, it was shown that the amorphization of (GeTe)x(Sb2Te3) films does not change the local environment of antimony and tellurium atoms. [ABSTRACT FROM AUTHOR]

The valence state and local environment of atoms in Ge3Sb2Te6, Ge2Sb2Te5, GeSb2Te4, and GeSb4Te7 amorphous and crystalline films are determined by Mössbauer spectroscopy (MS) on isotopes 119Sn, 121Sb, and 125Te. In crystalline films, divalent germanium is located in octahedral positions in a rhombohedrally distorted NaCl-type of lattice, whereas in amorphous films, tetravalent germanium atoms form a tetrahedral system of chemical bonds. In all films, the nearest environment of germanium contains predominantly tellurium atoms. Trivalent antimony atoms in crystalline and amorphous films occupy two types of octahedral positions differing in the degree of distortion, and in the nearest environment of antimony there are tellurium atoms. Finally, in all films, the local structures of tellurium atoms correspond to tellurium structural units in the GeTe and Sb2Te3 compounds. [ABSTRACT FROM AUTHOR]

It is shown using Mössbauer spectroscopy on 119Sn, 121Sb, and 125Te isotopes that the local structure of germanium atoms changes during crystallization of amorphous Ge2Sb2Te5 films (tetrahedral symmetry changes to the octahedral one), whereas the environment of antimony and tellurium atoms remains the same (the environment of antimony atoms it close to that in the Sb2Te3 compound). [ABSTRACT FROM AUTHOR]

Using Messbauer spectroscopy on 119Sn impurity atoms, it was demonstrated that in amorphous (GeTe)x(Sb2Te3) films (where x = 0.5, 1, 2, 3) tin atoms replace atoms of tetravalent germanium, which forms a tetrahedral system of chemical bonds with atoms in its local environment. In crystalline films, tin replaces divalent six-coordinated germanium in positions 4b of the NaCl-type crystal lattice. [ABSTRACT FROM AUTHOR]

method of standards has been proposed for determining the quantitative contents of germanium, arsenic, and selenium in vitreous samples and films of the AsSe and GeSe compositions with the use of X-ray fluorescence analysis. The application of this technique makes it possible to determine the quantitative composition of AsSe and GeSe glasses and films with an accuracy of ±0.001 with respect to the parameter x. [ABSTRACT FROM AUTHOR]

The method of Mössbauer spectroscopy of the isotope [sup 119]Sn is used to show that in PbS and PbSe an isoelectronic germanium impurity is a two-electron donor, and that the energy levels of germanium lie above the levels formed by tin impurity atoms in these semiconductors. [ABSTRACT FROM AUTHOR]