Cesium tungstate, also known as cesium tungsten oxide, is a colorless crystal with strong hygroscopicity. It can be prepared by the reaction of cesium chloride (CsCl) with silver tungstate (Ag2WO4). Its chemical formula is Cs2WO4, the molecular weight is 513.64900, and the CAS number is 13587-19-4.
The phase transformation of Cs2WO4 occurs at 536°C, transition from orthorhombic crystal to hexagonal crystal. 
Hazard
1. Usually, it is slightly harmful to water. Cs2WO4 can be soluble in water and react with acid and alkali, which will result in pollution to environment.
2. Cs2WO4 has acute toxicity, it may cause irritant effect. It may cause inflammation if contact with skin and eyes.
Storage
It should be placed under normal temperature and pressure and avoid to get contact with water, acid and alkali. Ensure that it is placed in a cool, ventilated and dry place to avoid accidental contact and result in harm.
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