Samarium disilicide
Chemical compound
From Wikipedia, the free encyclopedia
Samarium disilicide is a binary inorganic compound of samarium and silicon with the chemical formula SmSi2.[1][2]
| Names | |
|---|---|
| Other names
Samarium silicide, samarium(II) silicide | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.032.324 |
| EC Number |
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CompTox Dashboard (EPA) |
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| Properties | |
| Si2Sm | |
| Molar mass | 206.53 g·mol−1 |
| Appearance | Crystals |
| Density | 7.54 g/cm3 |
| insoluble | |
| Structure | |
| Orthorhombic | |
| α-SmSi2 orthorhombic β-SmSi2 tetragonal | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Synthesis
SmSi2 is prepared by reducing samarium oxide with silicon in vacuum at 1550-1600 °C.
Physical properties
Samarium disilicide exists in two crystalline modifications: α-SmSi2 and β-SmSi2, with lattices of the YSi2 orthorhombic (space group I mma) and ThSi2 tetragonal (space group I41/amd.[3]) types respectively and a transformation temperature of 380 °C.[4]
The compound melts congruently at a temperature of ≈1800 °C.[5]