TlAsS2

TlAsS2 is a ternary chalcogenide compound composed of thallium, arsenic, and sulfur with the chemical formula TlAsS2. It is part of the family of Tl-chalcogenide materials that have attracted interest for their semiconducting and nonlinear optical properties.

Preparation and structure: TlAsS2 can be synthesized by solid-state reaction of thallium sulfide-arsenide mixtures, such as Tl2S3 and As2S3, or by direct combination of Tl2S with As2S3 at high temperatures in evacuated sealed environments. The resulting crystals are typically studied as single crystals or polycrystalline samples. Reported crystal structures can vary with synthesis conditions, and monoclinic and orthorhombic polymorphs have been observed in different investigations.

Properties and applications: TlAsS2 behaves as a semiconductor and has been investigated for its nonlinear optical properties, including potential for second-harmonic generation and other photonic applications. Its optoelectronic behavior, such as photoconductivity and optical response across the visible to near-infrared range, depends on stoichiometry and crystal structure. Because it is a ternary compound containing toxic elements, its properties are typically explored in controlled laboratory settings.

Safety and handling: The material contains thallium and arsenic, both of which are highly toxic. Proper safety precautions are essential, including appropriate handling, containment, and waste disposal in accordance with relevant regulations.

Notes: TlAsS2 is primarily encountered in research contexts as a laboratory-synthesized material rather than a widely available commercial product. It illustrates the broader interest in ternary chalcogenides for semiconducting and nonlinear optical applications.