Silicon iodide
Encyclopedia
Silicon tetraiodide is the chemical compound
with the formula Si
I4
. 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
.
.
It can be made on a large scale by reaction of silicon or silicon carbide
with iodine on heating to about 200oC. Of more academic interest is the reaction of silane
with iodine vapour at 130 - 150oC, 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.
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
with the formula Si
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
I4
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....
. 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
Microelectronics
Microelectronics is a subfield of electronics. As the name suggests, microelectronics relates to the study and manufacture of very small electronic components. Usually, but not always, this means micrometre-scale or smaller,. These devices are made from semiconductors...
.
Reactions
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 tetrachlorideSilicon tetrachloride
Silicon tetrachloride is the inorganic compound with the formula SiCl4. It is a colourless volatile liquid that fumes in air. It is used to produce high purity silicon and silica for commercial applications.-Preparation:...
.
It can be made on a large scale by reaction of silicon or silicon carbide
Silicon carbide
Silicon carbide , also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass-produced since 1893 for use as an abrasive...
with iodine on heating to about 200oC. Of more academic interest is the reaction of silane
Silane
Silane is a toxic, extremely flammable chemical compound with chemical formula SiH4. In 1857, the German chemists and Friedrich Woehler discovered silane among the products formed by the action of hydrochloric acid on aluminum silicide, which they had previously prepared...
with iodine vapour at 130 - 150oC, 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
Iodoform
Iodoform is the organoiodine compound with the formula CHI3. A pale yellow, crystalline, volatile substance, it has a penetrating odor and, analogous to chloroform, sweetish taste. It is occasionally used as a disinfectant...
which is a yellow solid at room temperature.