Structural and Mössbauer study of (Sb0.70Te0.30)100-x Snx alloys with x = 0, 2.5, 5.0 and 7.5

ROCCA, J.A.; BILOVOL, V.; ERRANDONEA, D.; REBAZA, A.V. GIL; NAVARRO, A.M. MUDARRA; CHANDUVÍ, H.H. MEDINA; ERRICO, L.A.; ARCONDO, B.; FONTANA, M.; RODRÍGUEZ, O. CUELLAR; UREÑA, M.A.

JOURNAL OF ALLOYS AND COMPOUNDS

ELSEVIER SCIENCE SA

Año: 2019 vol. 795 p. 27 - 33

0925-8388

(Sb 0.70 Te 0.30 ) 100-x Sn x alloys (with x ¼ 0, 2.5, 5.0 and 7.5 at. %) have been synthesized and characterized inorder to determine the crystalline structure and properties of materials obtained upon solidification andto extract information about the location of the Sn atom in the Sb-Te matrix. Powder X-ray diffraction? ssbauer spectroscopy has been(XRD) has been used to determine the crystalline structure, whereas M outilized to determine the localization and the local structure of the Sn atom in the Sb-Te matrix throughthe hyperfine interactions of the 119 Sn probe with its environment. We found that Sb 70 Te 30 crystallizes ina trigonal structure belonging to P-3m1 space group, while the doping with Sn leads to structural dis-tortions of the unit cell that can be described, for all the Sn concentrations, with the C2/m space group.The hyperfine parameters indicate that tin behaves as Sn(II) and has a slightly distorted environment.Finally, in order to extract all the information that the experimental results contain and to determine thepreferential site occupied by the Sn impurities in the Sb-Te matrix, we have performed ab-initio calcu-lations within the framework of the Density Functional Theory. The theoretical results enable us todetermine the structural and electronic ground state of (Sb 0.70 Te 0.30 ) 100-x Sn x compounds and to confirmthat Sn atoms substitute Sb atoms in the Sb-Te host.