Barium tungstate

Barium tungstate is an inorganic chemical compound of barium and the tungstate anion.

Barium tungstate

Names
Other names Barium wolframate Tungstate white Wolfram white
Identifiers
CAS Number	7787-42-0
3D model (JSmol)	Interactive image
ChemSpider	145169
ECHA InfoCard	100.029.195
EC Number	232-114-3
PubChem CID	4280986
InChI InChI=1S/Ba.4O.W/q+2;;;2*-1; Key: SJPVUFMOBDBTHQ-UHFFFAOYSA-N
SMILES [O-][W](=O)(=O)[O-].[Ba+2]
Properties[1]
Chemical formula	BaWO4
Molar mass	385.16 g·mol−1
Appearance	white solid
Density	5.04 g·cm−3 (25 °C) 7.26 g·cm−3 (high pressure form)[2]
Melting point	1502 °C[3]
Solubility in water	insoluble
Structure[4]
Crystal structure	tetragonal
Lattice constant	a = 561.4 pm, c = 1271.5 pm
Hazards
GHS labelling:[1]
Pictograms
Hazard statements	H302, H332
Related compounds
Related compounds	Radium tungstate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis and properties

Barium tungstate can be obtained from the precipitation reaction between barium nitrate and ammonium paratungstate or sodium tungstate.^[5][6]

Ba(NO₃)₂ + Na₂WO₄ → BaWO₄↓ + 2 NaNO₃

It is a white solid,^[1] which at normal conditions forms tetragonal crystals similar to scheelite, CaWO₄. Under pressures above 7 GPa, the compound undergoes transformation to a monoclinic structure similar to fergusonite, YNbO₄.^[7]

Uses

Barium tungstate can be used as a frequency shifter in laser technology.^[8] It has uses in X-ray photography and as a pigment.^[4]