Tl — Properties & Data | MatWorld

Tl

metal

· Tl

Thallium (Tl) is a soft, dense post-transition metal with low melting point and high toxicity, belonging to Group 13 of the periodic table. Historically used in specialized optical applications (infrared lenses, scintillation detectors) and legacy electronics, thallium has largely been phased out of most industrial applications due to severe health and environmental hazards; modern engineering selection favors safer alternatives. When encountered in active use, it typically appears in niche scientific instrumentation, certain photomultiplier tubes, or specialized research contexts where its unique optical and radiation properties justify the toxicity risks and regulatory constraints.

infrared optics and windowsradiation detection equipmentlegacy semiconductor researchspecialized scintillation detectorsresearch-phase applications only

Compliance & Regulations

?EAR?Conflict Free?RoHS?REACH?TSCA?Prop 65

Units:

si imperial

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Method

Property	Value	Unit	Conditions
Bulk Modulus(K)2 entries	30.66	GPa	DFT · OptB88vdW
↳	26.38	GPa	DFT · PBE
Elastic Compliance Tensor(Sij)	Matrix (redacted)	1/GPa	DFT · PBE
Elastic Anisotropy(AU)	0.5403	-	DFT · PBE
Elastic Stiffness Tensor(Cij)	Matrix (redacted)	Pa	DFT · PBE
Poisson's Ratio(ν)2 entries	0.4100	-	DFT · OptB88vdW
↳	0.3809	-	DFT · PBE
Shear Modulus(G)2 entries	6.450	GPa	DFT · OptB88vdW
↳	6.823	GPa	DFT · PBE

N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form, heat treatment, basis, or test environment.

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Density(ρ)	11.10	kg/m³	DFT · OptB88vdW

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Method

Carrier

Property	Value	Unit	Conditions
Band Gap(Eg)2 entries	0.000	eV	DFT · OptB88vdW
↳	0.000	eV	DFT · TBmBJ
Magnetic Moment(μB)	0.000	µB	DFT · OptB88vdW
Thermoelectric Power Factor(PF)2 entries	0.000151	W/(m·K²)	DFT · OptB88vdW · n-type · 1e20 cm⁻³ · 327°C
↳	0.000133	W/(m·K²)	DFT · OptB88vdW · p-type · 1e20 cm⁻³ · 327°C
Seebeck Coefficient(S)2 entries	-3.820	μV/K	DFT · OptB88vdW · n-type · 1e20 cm⁻³ · 327°C
↳	-3.590	μV/K	DFT · OptB88vdW · p-type · 1e20 cm⁻³ · 327°C

N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form, heat treatment, basis, or test environment.

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Energy Above Hull(ΔEhull)	0.000	eV/atom	DFT · OptB88vdW
Formation Energy(ΔHf)	0.000	eV/atom	DFT · OptB88vdW

Verified Unverified Low confidence (<80%) Link to source

Reference data from cited sources. Not verified or certified by MatWorld Inc. Verify against the source before use in design. Terms: engineering data

Regulatory Screening

Environmental

Export Control

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.

Tl

Mechanical Properties

Physical Properties

Electrical Properties

Other Properties

Regulatory Screening

Environmental

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