CompoundList
Sign in
Metals, alloys and elements

Thallium-203

Also known as 203Tl isotope, Tl-203 isotope, Thallium, isotope of mass 203

CAS 14280-48-9Formula TlMolar mass 202.97 g/molEC 111-159-1
GHS signal word: Danger. Pictograms: Acute toxicity (severe), Serious health hazard
Get quotes Safety data
Element with atomic number and standard atomic weight

Key facts

What buyers check first

All properties
CAS number
14280-48-9
Formula
Tl
Molar mass
202.97 g/mol
EC number
111-159-1
HS code
284443
Category
Metals, alloys and elements

What is Thallium-203?

Plain description, key identifiers and synonyms

Thallium-203 is the stable isotope of thallium with relative atomic mass 202.9723. The least abundant (29.524 atom percent) isotope of naturally occurring thallium.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
thallium-203
CAS number
14280-48-9
EC number
111-159-1
Molecular formula
Tl
InChIKey
BKVIYDNLLOSFOA-BJUDXGSMSA-N
InChI
InChI=1S/Tl/i1-1
Canonical SMILES
[Tl]
Isomeric SMILES
[203Tl]

Synonyms

  • 203Tl isotope
  • Tl-203 isotope
  • Thallium, isotope of mass 203
  • (203)Tl
  • (203)81Tl
  • Thallium-203 isotope
  • Isotope:203Tl
  • 203Tl (isotope)
  • Isotope:Thallium-203
  • (~203~Tl)Thallium

Physical and chemical properties

Measured values and descriptors computed from the structure

Physical and chemical properties

Measured values, check the supplier specification for your grade

No measured properties are recorded for this substance yet. Ask suppliers for a technical data sheet.

Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.

Computed descriptors

Calculated from the structure, useful for screening and formulation

Molecular weight
202.97 g/molcalc.
Exact mass
202.9723 Dacalc.
LogP (octanol/water)
-0.38calc.
Topological polar surface area
0 Ųcalc.
Hydrogen bond donors
0calc.
Hydrogen bond acceptors
0calc.
Rotatable bonds
0calc.
Heavy atoms
1calc.
Rings
0calc.
Aromatic rings
0calc.
Fraction sp3 carbons
0calc.
Formal charge
0calc.
Stereocentres
0calc.

Calculated for screening. Confirm critical figures with the supplier.

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Danger
GHS06: Acute toxicity (severe)
Acute toxicity (severe)
GHS08: Serious health hazard
Serious health hazard

Hazard statements

  • H302Harmful if swallowed.
  • H330Fatal if inhaled.
  • H373May cause damage to organs through prolonged or repeated exposure.
  • H413May cause long lasting harmful effects to aquatic life.
Precautionary statements (15)
  • P260Do not breathe dust, fume, gas, mist, vapours or spray.
  • P264Wash skin thoroughly after handling.
  • P270Do not eat, drink or smoke when using this product.
  • P271Use only outdoors or in a well-ventilated area.
  • P273Avoid release to the environment.
  • P284In case of inadequate ventilation wear respiratory protection.
  • P301 + P317If swallowed: Get medical help.
  • P304 + P340If inhaled: Remove person to fresh air and keep comfortable for breathing.
  • P316Get emergency medical help immediately.
  • P319Get medical help if you feel unwell.
  • P320Specific treatment is urgent (see supplemental first aid instructions on the label).
  • P330Rinse mouth.
  • P403 + P233Store in a well-ventilated place. Keep container tightly closed.
  • P405Store locked up.
  • P501Dispose of contents and container in accordance with local regulations.

GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.

Full safety data and first aid

Thallium-203 suppliers

Sponsored listings first, then the documented ranking: membership, verification, replies, completeness, freshness and ratings

No supplier listings yet

Post one free request and suppliers who make or trade Thallium-203 can send you quotes. Your contact details stay private until you accept a quote.

Request quotesSell this chemical

Thallium-203 price

Indicative price range per kg from live supplier offers

No published prices right now

Suppliers quote this chemical on request. Send one free request and compare quotes side by side.

Get latest price

Uses and applications

What the substance is used for, by industry and function

Regulatory status

Inventories, regulations and trade controls that list this substance

No regulatory list memberships are recorded for this substance yet. Always check the rules of the importing and exporting country before trade.

HS code and trade data

Customs classification and reported world trade statistics

Global trade

World import and export statistics for the HS code Thallium-203 is traded under.

HS 2844.43Indicative HS code

Radioactive elements and isotopes and compounds other than those of subheading 284410…

World exports in 2024
$2.19B
+8.8% vs 2023, imports $2.53B
2022 to 2024
Top exporters
  1. Canada32.1%
  2. Netherlands17.0%
  3. Germany11.4%
Top importers
  1. United States37.8%
  2. Germany8.4%
  3. China5.8%
Reported customs values in USD, not prices.Full trade data

The HS code shown for Thallium-203 is indicative (it is known at chapter level only). Confirm the classification with your customs broker before shipping.

Frequently asked questions

Quick answers about Thallium-203, based on the data on this page

What is Thallium-203?

Thallium-203 is the stable isotope of thallium with relative atomic mass 202.9723. The least abundant (29.524 atom percent) isotope of naturally occurring thallium.

What is the CAS number of Thallium-203?

The CAS registry number of Thallium-203 is 14280-48-9.

What is the molecular formula and weight of Thallium-203?

The molecular formula of Thallium-203 is Tl and its molar mass is 202.97 g/mol.

What is Thallium-203 used for?

Known uses and roles of Thallium-203 include isotope-labelled compounds in research and laboratory.

Is Thallium-203 hazardous?

Thallium-203 carries the GHS signal word "Danger". Main hazards: harmful if swallowed, fatal if inhaled, may cause damage to organs through prolonged or repeated exposure. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of Thallium-203?

Thallium-203 is usually classified under HS code 284443 (Radioactive elements and isotopes and compounds other than those of subheading 284410…). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Thallium-203?

Post a free request on CompoundList and suppliers of Thallium-203 will send you quotes. Your contact details stay private until you accept a quote.

What is the price of Thallium-203?

Suppliers quote Thallium-203 on request because prices depend on grade, purity, quantity and destination. A free request on CompoundList gets you several quotes to compare.

Guides for buyers

Practical guides that help when you source, ship or handle Thallium-203

Get quotes for Thallium-203

Post one free request with your grade, quantity and destination. Matching suppliers send quotes you can compare side by side.
Post a request Sell Thallium-203
Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
Embed this structure on your websiteShow code

Paste this code into your page to show the 2D structure of Thallium-203 with a 3D view, its CAS number where known and a link back to this page. Free to use with the link kept.

<iframe src="https://www.compoundlist.com/embed/structure/thallium-203-14280-48-9" title="Thallium-203 structure on CompoundList" width="360" height="420" style="border:1px solid #E7E2DA;border-radius:12px;max-width:100%" loading="lazy" referrerpolicy="strict-origin-when-cross-origin"></iframe>
Preview the embed

Explore more in Metals, alloys and elements or HS code 284443

Price on request
Free quotes, contact stays private
Get quotes