Silicon tetraiodide

Silicon tetraiodide

Names
Other names silicon tetraiodide Tetraiodosilane
Identifiers
CAS Number	13465-84-4 N
3D model (Jmol)	Interactive image
ChemSpider	75335 Y
ECHA InfoCard	100.033.355
PubChem	83498
InChI InChI=1S/I4Si/c1-5(2,3)4 Y Key: CFTHARXEQHJSEH-UHFFFAOYSA-N Y InChI=1/I4Si/c1-5(2,3)4 Key: CFTHARXEQHJSEH-UHFFFAOYAL
SMILES I[Si](I)(I)I
Properties
Chemical formula	SiI4
Molar mass	535.7034 g/mol
Appearance	white powder
Density	4.198 g/cm3
Melting point	120.5 °C (248.9 °F; 393.6 K)
Boiling point	287.4 °C (549.3 °F; 560.5 K)
Solubility in water	insoluble
Solubility in organic solvents	soluble
Structure
Molecular shape	tetrahedral
Hazards
EU classification (DSD)	not listed
R-phrases	R61-R24/25-R34-R42/43
S-phrases	S53-S26-S36/37/39-S45
NFPA 704	0 2 0
Flash point	−18 °C (0 °F; 255 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Silicon tetraiodide is the chemical compound with the formula SiI₄. It is a tetrahedral molecule with Si-I bond lengths of 2.432(5) Å.

SiI₄ is a precursor to silicon amides of the formula Si(NR₂)₄ (R = alkyl). It has also been of interest in the manufacture and etching of silicon in microelectronics.

The compound is stable to strong heating and can be stored for long periods at room temperature but must be kept dry as it reacts quickly with water and also reacts slowly with moisture in the air in a similar way to silicon tetrachloride. It can be made on a large scale by reaction of silicon or silicon carbide with iodine on heating to about 200 °C. Of more academic interest is the reaction of silane with iodine vapour at 130 - 150 °C, as this produces a series of compounds ranging from iodosilane SiH₃I to diiodosilane SiH₂I₂ and triiodosilane SiHI₃ as well. These compounds are colourless liquids at room temperature. The last one can be readily distinguished from the similar carbon compound, iodoform which is a yellow solid at room temperature.