Tl2S
thallium(I) sulfide · thallous sulfide
Thallium(I) sulfide is a stable semiconducting compound frequently investigated for its utility in infrared sensing and optical applications.
About thallium(I) sulfide
Thallium(I) sulfide is a distinct binary chalcogenide that exists as a thermodynamically stable phase on the convex hull. Its electronic character as a semiconductor makes it a subject of interest for specialized optoelectronic research and material characterization studies.
With a significant number of reported structures across various databases, this compound demonstrates a complex structural landscape. It is primarily utilized in the development of sensitive infrared detection equipment and specialized optical components where its unique electronic properties can be leveraged.
Key Properties
Cross-validated computational properties for thallium(I) sulfide, aggregated across 3 databases.
Band GapEnergy needed to move an electron from the valence band to the conduction band. Lower or zero values tend to behave more metallic; larger gaps are more insulating or semiconducting.
Energy Above HullThermodynamic distance from the most stable set of competing phases. 0 eV/atom is on the convex hull; small positive values may still be experimentally accessible.
StabilityA plain-language summary of the best reported energy-above-hull result. It reflects whether the lowest-energy structure is on, near, or far from the stability hull.
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
Cross-Source DFT Agreement
How well independent DFT databases agree on the thermodynamics of Tl2S. Tight agreement means computed properties can be trusted without re-running calculations.
Agreement ScoreA normalized confidence score summarizing how closely independent DFT databases agree. Higher scores mean tighter cross-source agreement.
Hull SpreadDifference between the highest and lowest energy-above-hull values reported by comparable sources. Smaller spread means less thermodynamic disagreement.
Sources ComparedNumber and names of computational sources with comparable entries for this formula.
Space Group ConsensusWhether independent sources predict the same crystal symmetry for the lowest-energy structure.
Reported Structures
Lowest-energy structures reported for Tl2S, ranked by energy above hull.
| Space GroupSymmetry classification of the crystal arrangement. The number is the international space-group index. | Crystal SystemBroad lattice family, such as cubic, tetragonal, monoclinic, or triclinic, derived from unit-cell symmetry. | Band Gap (eV)Electronic gap calculated for this specific reported structure, measured in electronvolts. | E above hull (eV/atom)Thermodynamic distance from the convex hull for this structure, normalized per atom. Lower is generally more stable. | E/atom (eV)Computed total energy normalized per atom. Use energy above hull, not this value alone, when comparing stability. | Density (g/cm³)Mass per relaxed crystal volume, reported in grams per cubic centimeter. |
|---|---|---|---|---|---|
| P3 (No. 143) | trigonal | 0.98 | 0.0000 | -0.394 | — |
| — | — | 0.90 | 0.0000 | -0.445 | — |
| R3 (No. 146) | trigonal | 0.77 | 0.0000 | -3.465 | 7.50 |
| P31m (No. 157) | trigonal | 1.13 | 0.0002 | -38.555 | 7.94 |
| — | — | 0.85 | 0.0008 | -0.444 | — |
| R3 (No. 146) | trigonal | 0.59 | 0.0011 | -3.464 | 7.99 |
| P3 (No. 143) | trigonal | 1.28 | 0.0015 | -3.464 | 7.96 |
| — | — | 0.86 | 0.0016 | -0.443 | — |
| — | — | 0.00 | 0.0017 | -0.443 | — |
| — | — | 0.57 | 0.0068 | -0.438 | — |
| — | — | 0.20 | 0.0092 | -0.436 | — |
| — | — | 0.00 | 0.0515 | -0.393 | — |
Applications
Where thallium(I) sulfide is used.
Frequently Asked Questions
Common questions about thallium(I) sulfide, answered from cross-validated data.
What is Tl2S?
Thallium(I) sulfide is a stable semiconducting compound frequently investigated for its utility in infrared sensing and optical applications.
What is Tl2S used for?
What is the band gap of Tl2S?
Is Tl2S a metal, semiconductor, or insulator?
Is Tl2S thermodynamically stable?
What is the crystal structure of Tl2S?
What is the density of Tl2S?
How many polymorphs of Tl2S are known?
What elements does Tl2S contain?
Where does the data for Tl2S come from?
How It Compares
As a standalone binary chalcogenide, thallium(I) sulfide serves as a fundamental reference point for understanding the behavior of heavy-metal sulfides. It occupies a unique position in materials science due to its stability and semiconducting nature, which distinguish it from more common, less stable thallium-based compounds.
Data sources & attribution
- jarvis — Data from JARVIS (jarvis.nist.gov), NIST. Cite: Choudhary et al., npj Comp. Mater. 6, 173 (2020). (LicenseRef-US-Gov-PD)
- oqmd — Data from the OQMD (oqmd.org). Cite: Saal et al., JOM 65, 1501 (2013); Kirklin et al., npj Comp. Mater. 1, 15010 (2015). (CC-BY-4.0)
- materials_project — Data from the Materials Project (materialsproject.org). Cite: Jain et al., APL Materials 1, 011002 (2013). (CC-BY-4.0)
- mpaloe — Data from MP-ALOE. Cite: Kuner et al., npj Comput. Mater. (2025), doi:10.1038/s41524-025-01834-9.
- cod — Data from the Crystallography Open Database (crystallography.net/cod/). Cite: Grazulis et al., J. Appl. Cryst. 42, 726 (2009). (CC0-1.0)
Analyze Tl2S in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 85 source databases.
Explore the Platform →