Caesium perchlorate

Caesium perchlorate, CsClO4 (also known as cesium perchlorate), is a perchlorate of caesium. It forms white hygroscopic crystals in the solid state soluble in water and alcohol.

Under temperature 219 °C it has orthorhombic structure Pnma with lattice constants a = 9.82, b = 6.00, c = 7.79 (.10-1 nm). Above 219 °C it crystallizes in cubic crystallic structure F43m with lattice constant a = 7.98. 10-1 nm.

CsClO4 is the least soluble of the alkali metal perchlorates (followed by Rb, K, Li, and Na), a property which may be used for separatory purposes and even for gravimetric analysis. This low solubility is attributed to the formation of aggregates between the metal atom and the perchlorate anion.

Table of solubility in water :

When heated, CsClO4 decomposes to CsCl at 575 °C. Like all perchlorates, it is a strong oxidant and may react violently with reducing agents and organic materials, especially at elevated temperatures.

Caesium perchlorate helped in discovering francium and identifying it as an alkali metal because francium-223 coprecipitated with cesium perchlorate.