The structure of the binary chalcogenide crystalline Tl−Se system

Abstract

X-ray diffraction studies for sixteen compositions of recrystallized samples for Tl _x Se_1−x system, withx=0.0 up tox=0.9, shows the existence of four crystalline phases. Crystalline hexagonal selenium exists in the range ofx=0.0 tox=0.4, which is a glass region boundary, indicating the responsibility of selenium for forming Se−Tl glasses. Tetragonal SeTl crystalline phase exists in the wide range ofx=0.005 tox=0.9, and tetragonal SeTl₂ crystalline phase was observed in the range ofx=0.58 tox=0.9. The α-thallium hexagonal phase was observed in the range ofx=0.7 tox=0.9. The effect of thallium content on the interplanar spacing (d _hkl) and relative intensities (I/I ₀) of the diffraction lines of elemental selenium is reported.