Caesium chloride

Caesium chloride

Names
IUPAC name Caesium chloride
Other names Cesium chloride
Identifiers
CAS Number	7647-17-8 Y
3D model (JSmol)	Interactive image
ChemSpider	22713 Y
ECHA InfoCard	100.028.728
EC Number	231-600-2
PubChem CID	24293
UNII	GNR9HML8BA Y
CompTox Dashboard (EPA)	DTXSID3040435
InChI InChI=1S/ClH.Cs/h1H;/q;+1/p-1 Y Key: AIYUHDOJVYHVIT-UHFFFAOYSA-M Y InChI=1/ClH.Cs/h1H;/q;+1/p-1 Key: AIYUHDOJVYHWHXWOFAO
SMILES [Cs+].[Cl-]
Properties
Chemical formula	CsCl
Molar mass	168.36 g/mol
Appearance	white solid hygroscopic
Density	3.988 g/cm3[1]
Melting point	646 °C (1,195 °F; 919 K)[1]
Boiling point	1,297 °C (2,367 °F; 1,570 K)[1]
Solubility in water	1910 g/L (25 °C)[1]
Solubility	soluble in ethanol[1]
Band gap	8.35 eV (80 K)[2]
Magnetic susceptibility (χ)	-56.7·10−6 cm3/mol[3]
Refractive index (nD)	1.712 (0.3 μm) 1.640 (0.59 μm) 1.631 (0.75 μm) 1.626 (1 μm) 1.616 (5 μm) 1.563 (20 μm)[4]
Structure
Crystal structure	CsCl, cP2
Space group	Pm3m, No. 221[5]
Lattice constant	a = 0.4119 nm
Lattice volume (V)	0.0699 nm3
Formula units (Z)	1
Coordination geometry	Cubic (Cs+) Cubic (Cl−)
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H341, H361, H373
Precautionary statements	P201, P202, P260, P264, P270, P281, P301+P312, P308+P313, P314, P330, P405, P501
Lethal dose or concentration (LD, LC):
LD50 (median dose)	2600 mg/kg (oral, rat)[6]
Related compounds
Other anions	Caesium fluoride Caesium bromide Caesium iodide Caesium astatide
Other cations	Lithium chloride Sodium chloride Potassium chloride Rubidium chloride Francium chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Caesium chloride or cesium chloride is the inorganic compound with the formula CsCl. This colorless salt is an important source of caesium ions in a variety of niche applications. Its crystal structure forms a major structural type where each caesium ion is coordinated by 8 chloride ions. Caesium chloride dissolves in water. CsCl changes to NaCl structure on heating. Caesium chloride occurs naturally as impurities in carnallite (up to 0.002%), sylvite and kainite. Less than 20 tonnes of CsCl is produced annually worldwide, mostly from a caesium-bearing mineral pollucite.^[7]

Caesium chloride is widely used in isopycnic centrifugation for separating various types of DNA. It is a reagent in analytical chemistry, where it is used to identify ions by the color and morphology of the precipitate. When enriched in radioisotopes, such as ¹³⁷CsCl or ¹³¹CsCl, caesium chloride is used in nuclear medicine applications such as treatment of cancer and diagnosis of myocardial infarction. Another form of cancer treatment was studied using conventional non-radioactive CsCl. Whereas conventional caesium chloride has a rather low toxicity to humans and animals, the radioactive form easily contaminates the environment due to the high solubility of CsCl in water. Spread of ¹³⁷CsCl powder from a 93-gram container in 1987 in Goiânia, Brazil, resulted in one of the worst-ever radiation spill accidents killing four and directly affecting 249 people.