THALLIUM(I) IODIDE Chemical Properties

Melting point:

440 °C(lit.)

Boiling point:

823°C

Density 

7.29 g/mL at 25 °C(lit.)

Flash point:

824°C

storage temp. 

10-30°C

solubility 

insoluble in ethanol

form 

Powder

Specific Gravity

7.09

color 

Yellow

Water Solubility 

Practically insoluble in water

Sensitive 

Light Sensitive

Merck 

14,9264

Solubility Product Constant (Ksp)

pKsp: 7.26

Exposure limits

ACGIH: TWA 0.02 mg/m3 (Skin)

InChI

1S/HI.Tl/h1H;/q;+1/p-1

InChIKey

CMJCEVKJYRZMIA-UHFFFAOYSA-M

SMILES

I[Tl]

CAS DataBase Reference

7790-30-9(CAS DataBase Reference)

EPA Substance Registry System

Thallium iodide (TlI) (7790-30-9)

Safety Information

Hazard Codes 

T+,N

Risk Statements 

26/28-33-51/53

Safety Statements 

13-28-45-61

RIDADR 

UN 1707 6.1/PG 2

WGK Germany 

3

RTECS 

XG5425000

TSCA 

TSCA listed

HazardClass 

6.1

PackingGroup 

II

Storage Class

6.1A - Combustible acute toxic Cat. 1 and 2
very toxic hazardous materials

Hazard Classifications

Acute Tox. 2 Inhalation
Acute Tox. 2 Oral
Aquatic Chronic 2
STOT RE 2

MSDS

• Language:English Provider:SigmaAldrich
• Language:English Provider:ALFA

THALLIUM(I) IODIDE Usage And Synthesis

Description

Thallium (I) iodide is a yellow solid, nearly insoluble in water. It is used as infrared radiation transmitter (crystals mixed with thallium bromide).

Chemical Properties

Yellow powder. Insoluble in alcohol; slightly soluble in water; soluble in aqua regia.

Uses

Mixed crystals with thallium bromide for infrared radiation transmitters.

Uses

Thallium(I) iodide is used in mercury lamp to enhance its performance. It is mainly used for underwater lighting, since the blue green light produced has least absorption in water. Scintillator made by using iodide salt of thallium, sodium and cesium is utilized for radiation scintillation detectors.

Safety Profile

Poison by ingestion and subcutaneous routes. Human systemic effects: blood pressure lowering, change in motor activity, muscle weakness. When heated to decomposition it emits very toxic fumes of T1 and I-. See also IODIDES and THALLIUM COMPOUNDS.

Synthesis

T1I, also known as thallium(I) iodide can be made using a direct reaction between thallium and iodine, but it is usually precipitated by adding thallium salts (sulfates, perchlorates) to an aqueous solution of potassium iodide or hydriodic acid, washed with water, and then dried at 110 ??C. Thallium iodide has two homogeneous isomers that will undergo reversible phase transfer at 175??C or 4.7 GPa. The high-temperature type is an isometric crystalline system with a cesium chloride-type body-centered cubic lattice, called β-T1I quasi-stable phase, and is red in color. The low-temperature type α-T1I is a rhombohedral crystal system and is yellow in color. It fluoresces by X-rays or light. Above 160 GPa it shows metallic conductivity. Although stable in dilute hydrochloric and dilute sulfuric acids, it reacts with nitric acid to form iodine and thallium nitrate.

Purification Methods

Reflux it for 2-3hours with water containing HI, then wash it until acid-free, and dry it at 120o. Store it in brown bottles. [D.nges in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 870 1963]. POISONOUS.

THALLIUM(I) IODIDE(7790-30-9)Related Product Information

• THALLIUM(I) NITRATE
• CYCLOPENTADIENYLTHALLIUM
• THALLIUM(I) SULFATE
• THALLIUM(III) OXIDE
• THALLIUM(I) 2,4-PENTANEDIONATE
• THALLIC ACETATE SESQUIHYDRATE
• THALLIUM(I) FLUORIDE
• THALLIUM(III) TRIFLUOROACETATE
• THALLIUM (I) TRIFLUOROMETHANESULFONATE
• THALLIUM
• Thallium bromide iodide (TlBrI)
• THALLIUM(I) HEXAFLUOROACETYLACETONATE
• THALLIUM HEXAFLUOROPHOSPHATE
• THALLIUM HYDROTRIS[3-(2-PYRIDYL)PYRAZOL-1-YL]BORATE
• THALLIUM (I) 2-ETHYLHEXANOATE
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• THALLIUM(I) IODIDE
• THALLIUM IODIDE (IC)