Mg2Si crystallizes in the antifluorite structure. In the face-centered cubic lattice Si centers occupy the corners and face-centered positions of the unit cell and Mg centers occupy eight tetrahedral sites in the interior of the unit cell. The coordination numbers of Si and Mg are eight and four, respectively.[2]
Synthesis
The reaction of powdered sand with magnesium powder.
It can be produced by heating silicon dioxide, SiO2, found in sand, with excess magnesium. The process first forms silicon metal and magnesium oxide, and, if an excess of SiO2 is used, then elemental silicon is formed:
2 Mg + SiO2 → 2 MgO + Si
If an excess of Mg is present, Mg2Si is formed from the reaction of the remaining magnesium with the silicon:
2 Mg + Si → Mg2Si
These reactions proceed exothermically,[4] even explosively.[5]
Reactions
The reaction of magnesium silicide with 10% hydrochloric acid.
Magnesium silicide can be viewed as consisting of Si4− ions. As such it is reactive toward acids. Thus, when magnesium silicide is treated with hydrochloric acid, silane (SiH4) and magnesium chloride are produced:
Magnesium silicide is used to create aluminium alloys of the 6000 series, containing up to approximately 1.5% Mg2Si. An alloy of this group can be age-hardened to form Guinier-Preston zones and a very fine precipitate, both resulting in increased strength of the alloy.[6]
Magnesium silicide is a narrow-gap semiconductor. Its as-grown crystal exhibit n-type conductivity, but it can changed to p-type by doping with Ag, Ga, Sn and possibly Li (at high doping level). The major potential electronic application of Mg2Si is in thermoelectric generators.[3][7]
References
Wikimedia Commons has media related to Magnesium silicide.
^ abNoda Y., Kon H., Furukawa Y., Otsuka N., Nishida I.A., Masumoto K. (1992). "Preparation and Thermoelectric Properties of Mg2Si1−xGex (x=0.0∼0.4) Solid Solution Semiconductors". Mater. Trans., JIM. 33 (9): 845–850. doi:10.2320/matertrans1989.33.845.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^ abHirayama, Naomi (2019). "Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study". Sci. Technol. Adv. Mater. 20 (1): 160–172. Bibcode:2019STAdM..20..160H. doi:10.1080/14686996.2019.1580537. PMC6419642. PMID 30891103.
^Ehrlich, P. (1963) "Alkaline Earth Metals", p. 920 in Handbook of Preparative Inorganic Chemistry, 2nd ed., Vol. 1. G. Brauer (ed.). Academic Press, New York.
^ abStock, Alfred; Somieski, Carl (1916). "Siliciumwasserstoffe. I. Die aus Magnesiumsilicid und Säuren entstehenden Siliciumwasserstoffe". Berichte der Deutschen Chemischen Gesellschaft. 49: 111–157. doi:10.1002/cber.19160490114.
^"Properties and Selection: Non-ferrous Alloys and Special Purpose Materials" in ASM Handbook, 10th ed., Vol. 1, 1990, ASM International, Materials Park, Ohio. ISBN0871703785.
^Borisenko, Victor E. (2013). Semiconducting Silicides: Basics, Formation, Properties. Springer Science & Business Media. pp. 187, 287. ISBN978-3-642-59649-0.
January 06, 2023
magnesium, silicide, mg2si, inorganic, compound, consisting, magnesium, silicon, grown, mg2si, usually, forms, black, crystals, they, semiconductors, with, type, conductivity, have, potential, applications, thermoelectric, generators, namespreferred, iupac, na. Magnesium silicide Mg2Si is an inorganic compound consisting of magnesium and silicon As grown Mg2Si usually forms black crystals they are semiconductors with n type conductivity and have potential applications in thermoelectric generators 3 Magnesium silicide NamesPreferred IUPAC name Magnesium silicideIdentifiersCAS Number 22831 39 6 Y3D model JSmol Interactive imageChemSpider 81111 YECHA InfoCard 100 041 125EC Number 245 254 5PubChem CID 89858UNII 475E6FMG3K YUN number 2624CompTox Dashboard EPA DTXSID4066830InChI InChI 1S 2Mg Si YKey YTHCQFKNFVSQBC UHFFFAOYSA N YInChI 1 2Mg Si rMg2Si c1 3 2Key YTHCQFKNFVSQBC GEBTXNJDAASMILES Mg Si Mg PropertiesChemical formula Mg 2SiMolar mass 76 695 g mol 1Appearance Gray cubic crystals 1 Density 1 99 g cm 3 1 Melting point 1 102 C 2 016 F 1 375 K 1 Solubility in water reacts 1 Structure 2 Crystal structure Cubic cF12Space group Fm3 m 225Lattice constant a 0 6351 nmFormula units Z 4HazardsOccupational safety and health OHS OSH Main hazards reacts with water to produce pyrophoric silaneGHS labelling PictogramsSignal word WarningHazard statements H261Precautionary statements P231 P232 P280 P370 P378 P402 P404 P501Related compoundsOther cations Calcium silicideExcept where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Crystal structure 2 Synthesis 3 Reactions 4 Uses 5 ReferencesCrystal structure EditMg2Si crystallizes in the antifluorite structure In the face centered cubic lattice Si centers occupy the corners and face centered positions of the unit cell and Mg centers occupy eight tetrahedral sites in the interior of the unit cell The coordination numbers of Si and Mg are eight and four respectively 2 Synthesis Edit source source source source source source source source source source source source source source The reaction of powdered sand with magnesium powder It can be produced by heating silicon dioxide SiO2 found in sand with excess magnesium The process first forms silicon metal and magnesium oxide and if an excess of SiO2 is used then elemental silicon is formed 2 Mg SiO2 2 MgO SiIf an excess of Mg is present Mg2Si is formed from the reaction of the remaining magnesium with the silicon 2 Mg Si Mg2SiThese reactions proceed exothermically 4 even explosively 5 Reactions Edit source source source source source source source source source source source source source source The reaction of magnesium silicide with 10 hydrochloric acid Magnesium silicide can be viewed as consisting of Si4 ions As such it is reactive toward acids Thus when magnesium silicide is treated with hydrochloric acid silane SiH4 and magnesium chloride are produced Mg2Si 4 HCl SiH4 2 MgCl2Sulfuric acid can be used as well These protonolysis reactions are typical of a Group 2 alkaline earth metal and Group 1 alkali metal silicides The early development of silicon hydrides relied on this reaction 5 Uses EditMagnesium silicide is used to create aluminium alloys of the 6000 series containing up to approximately 1 5 Mg2Si An alloy of this group can be age hardened to form Guinier Preston zones and a very fine precipitate both resulting in increased strength of the alloy 6 Magnesium silicide is a narrow gap semiconductor Its as grown crystal exhibit n type conductivity but it can changed to p type by doping with Ag Ga Sn and possibly Li at high doping level The major potential electronic application of Mg2Si is in thermoelectric generators 3 7 References Edit Wikimedia Commons has media related to Magnesium silicide a b c d Haynes William M ed 2011 CRC Handbook of Chemistry and Physics 92nd ed Boca Raton FL CRC Press p 4 74 ISBN 1 4398 5511 0 a b Noda Y Kon H Furukawa Y Otsuka N Nishida I A Masumoto K 1992 Preparation and Thermoelectric Properties of Mg2Si1 xGex x 0 0 0 4 Solid Solution Semiconductors Mater Trans JIM 33 9 845 850 doi 10 2320 matertrans1989 33 845 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link a b Hirayama Naomi 2019 Substitutional and interstitial impurity p type doping of thermoelectric Mg2Si a theoretical study Sci Technol Adv Mater 20 1 160 172 Bibcode 2019STAdM 20 160H doi 10 1080 14686996 2019 1580537 PMC 6419642 PMID 30891103 Ehrlich P 1963 Alkaline Earth Metals p 920 in Handbook of Preparative Inorganic Chemistry 2nd ed Vol 1 G Brauer ed Academic Press New York a b Stock Alfred Somieski Carl 1916 Siliciumwasserstoffe I Die aus Magnesiumsilicid und Sauren entstehenden Siliciumwasserstoffe Berichte der Deutschen Chemischen Gesellschaft 49 111 157 doi 10 1002 cber 19160490114 Properties and Selection Non ferrous Alloys and Special Purpose Materials in ASM Handbook 10th ed Vol 1 1990 ASM International Materials Park Ohio ISBN 0871703785 Borisenko Victor E 2013 Semiconducting Silicides Basics Formation Properties Springer Science amp Business Media pp 187 287 ISBN 978 3 642 59649 0 Retrieved from https en wikipedia org w index php title Magnesium silicide amp oldid 1063437298, wikipedia, wiki, book, books, library,
