Bismuth silicon oxide

Bismuth silicon oxide or bismuth silicate refers to an inorganic compound of bismuth, silicon and oxygen. The bismuth silicate Bi₁₂SiO₂₀ is most commonly encountered, though others are also known. It occurs naturally as the mineral sillénite and can be produced synthetically by heating a mixture of bismuth oxide and silicon dioxide. Centimeter-sized single crystals of Bi₁₂SiO₂₀ can be grown by the Czochralski process from the molten phase. They exhibit piezoelectric, electro-optic, elasto-optic, photorefractive^[4] and photoconductive properties, and therefore have potential applications in spatial light modulators, acoustic delay lines and hologram recording equipment.^[1] Bi₁₂SiO₂₀ can be obtained as a whitish powder with band gap of approximately 3.2 eV starting from bismuth subcarbonate and silica in presence of ethyleneglycol.^{[5] 29}Si solid-state NMR is used to prove that the Si(IV) cations are sharing oxygen atoms with the Bi(III) cations. The ²⁹Si chemical shift (δ) in Bi₁₂SiO₂₀ is −78.1 ppm. Unlike bismuth oxide, the presence of the acidic Si(IV) cations avoid the reactivity with CO₂.^{[clarification needed]}

Bismuth silicon oxide

Bi12SiO20 crystal[1]
Bi12SiO20 crystal structure[2]
Names
Other names Sillénite Bismuth silicate
Identifiers
CAS Number	12377-72-9 Y
3D model (JSmol)	Interactive image
ChemSpider	23354126 Y
ECHA InfoCard	100.032.369
EC Number	235-620-2
PubChem CID	73555496
CompTox Dashboard (EPA)	DTXSID201014301
InChI InChI=1S/12Bi.O4Si.16O/c;;;;;;;;;;;;1-5(2,3)4;;;;;;;;;;;;;;;;/q12*+3;-4;16*-2 Key: JLXRQKOSFUIFEC-UHFFFAOYSA-N
SMILES [O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-] [Si]([O-])([O-])[O-].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3].[Bi+3]
Properties
Chemical formula	Bi12SiO20
Molar mass	2855.82
Odor	odorless
Density	9.20 g/cm3[2]
Melting point	800 °C[3]
Solubility in water	insoluble
Structure
Crystal structure	Body-centered cubic, cI66[2]
Space group	I23, No. 197
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Other bismuth silicates are known, such as Bi₄Si₃O₁₂, Bi₂SiO₅, and Bi₂Si₃O₉.^[6]