DEFECT STANNITE STRUCTURE AND CATION DISORDER IN THE TERNARY SEMICONDUCTOR ZnIn2Te4: RIETVELD REFINEMENT AND HIRSHFELD SURFACE ANALYSIS

Delgado G.E.; Cisterna J.; Mantilla J.C.; Chacón C.; Marroquin G.; Márquez G. · Romanian Journal of Physics (2026) · DOI: 10.59277/romjphys.2026.71.618

Resumen

ZnIn2Te4, a defect-derived ternary semiconductor belonging to the II-III2-VI4 family, was synthesized by a controlled melt and long-term annealing method and structurally characterized by powder X-ray diffraction combined with Rietveld refinement. The diffraction data were successfully indexed in a tetragonal unit cell and refined in the non-centrosymmetric space group I-42m, confirming a defect stannite-type structure. The refined unit cell parameters are a = 6.1506(1) Å and c = 12.3124(2) Å, with c/a ≈ 2.00, consistent with partial cation disorder between Zn2+ and In3+ over the 2a and 4d tetrahedral sites, while preserving the ordered cation vacancy required by electron-counting rules. The structure consists of slightly distorted corner-sharing (Zn/In)Te4 tetrahedra forming a three-dimensional framework. Hirshfeld surface and fingerprint plot analyses reveal that In-Te (46.4%) and Zn-Te (26.5%) contacts dominate the packing, whereas Te-Te interactions (20.6%) reflect the presence of intrinsic vacancies within the anion sublattice. Void surface analysis confirms the existence of isolated low-density regions associated with the defect-derived nature of the compound. The combined crystallographic and topological analyses provide a consistent structural model that rationalizes the reported spin-glass behavior in Mn-doped analogues and the intrinsically low lattice thermal conductivity predicted for this material, reinforcing the relevance of ZnIn2Te4 as a promising thermoelectric semiconductor.

Instituciones: Universidad Tecnológica del Perú