The Tl₂Se–HgSe–GeSe₂ system and the crystal structure of Tl₂HgGeSe₄

Chem. Met. Alloys 6 (2013) 55-62

https://doi.org/10.30970/cma6.0229

M.Yu. MOZOLYUK, L.V. PISKACH, A.O. FEDORCHUK, I.D. OLEKSEYUK, O.V. PARASYUK

The phase equilibria in the quasi-ternary system Tl₂Se–HgSe–GeSe₂ were investigated by differential-thermal analysis and X-ray diffraction. Phase diagrams of the Tl₂Se–HgSe and Tl₂GeSe₃–HgSe systems were constructed, as well as the isothermal section of the Tl₂Se–HgSe–GeSe₂ system at 520 K. Two intermediate quaternary compounds, Tl₂HgGeSe₄ and Tl₂HgGe₂Se₆, exist at this temperature. Tl₂HgGeSe₄ crystallizes in the non-centrosymmetric space group I-42m with the unit cell parameters a = 0.79947(4) nm, c = 0.67617(4) nm.

Location of metal atoms within the cubic anionic sub-lattice formed by germanium-centered tetrahedra of selenium atoms in the Tl₂HgGeSe₄ structure

Keywords

Chalcogenides / Semiconductors / X-ray diffraction / Crystal structure