Disorder and Transport Properties of In₃SbTe₂ – an X‐ray, Neutron and Electron Diffraction Study

Abstract

Abstract. Quenched metastable In 3 SbTe 2 was investigated by X-ray and neutron powder diffraction as well as by single-crystal X-ray diffraction. The average structure corresponds to the rocksalt type, the anion position being occupied by antimony and tellurium. Neutron data indicate no antisite disorder of indium and antimony. The compound is a high-temperature phase that can be quenched to yield a metastable compound at ambient temperature which, upon heating, decomposes at ca. 320°C into InSb and InTe. Diffuse scattering in reconstructed X-ray and selected area electron diffraction patterns indicates local

Influence of the exchange and correlation functional on the structure of amorphous InSb and In3SbTe2 compounds

“…The calculated Debye-Waller factor averaged over the three species at 300 K is about 1.67 Å 2 in the model at 5.554 g/cm 3 which is very close to the value of 1.52 Å 2 measured experimentally from the Rietveld analysis of the crystalline cubic phase of In 3 SbTe 2 in Ref. 42. However, we must consider that the latter experimental value includes the static displacement with respect to the ideal rocksalt geometry due to disorder.…”

“…In the lack of experimental information on the density we initially fixed the density of the liquid to the value 6.448 g/cm 3 (0.0323 atoms/Å 3 ) which is about 7% lower than the density of 6.96 g/cm 3 that can be assigned to the ideal rocksalt crystal with the experimental lattice parameter of 6.126(1) Å. 41,42 A similar increase in density upon crystallization of the amorphous is found in phase change GeSbTe alloys. 2 An amorphous model was then generated by quenching the liquid at fixed density from 1000 K to 300 K in about 250 ps.…”

“…42 The crystal is metallic with a conductivity of 3.2 · 10 4 S/cm at normal conditions. 42 In our previous work 15 we reported a theoretical equilibrium density about 10% lower than in experiments as computed from the equation of state of the cubic crystal in a 216-atom supercell with the PBE functional. In this calculation the Brillouin zone integration was restricted to the Γ-point only which, however, turns out to be insufficient given the metallic nature of the compound.…”

Exploring the applicability of amorphous films of system In-Sb-Te as phase change materials

“…Moreover, whereas for Ge 2 Sb 2 Te 5 (GST) the cation network (Ge, Sb) is disordered [15], in In 3 SbTe 2 the disordered network is the anion one (Sb,Te) [14]. On the other hand IST is stable at higher temperatures than GST and their crystallizations proceed following different stages presenting, each one, a characteristic resistivity.…”

“…In-Sb-Te system presents, as well as Ge-Sb-Te, a pseudo-binary alloy along InSb-InTe tie line [13] but in spite that InSb and InTe are characterised by tetrahedral nearest-neighbor environments for the cation, this pseudo binary alloy, In 3 SbTe 2 (IST), has metastable rock salt structure [14] with octahedral In environments. Moreover, whereas for Ge 2 Sb 2 Te 5 (GST) the cation network (Ge, Sb) is disordered [15], in In 3 SbTe 2 the disordered network is the anion one (Sb,Te) [14].…”