Caesium dichloroiodate, also called caesium dichloroiodide is an inorganic compound with the formula Cs[ICl2]. This yellow-orange salt is a crystalline solid in its pure form at room temperature. Fractional crystallization of caesium dichloroiodate may be used to separate caesium from rubidium and purify it, as rubidium dichloroiodate (Rb[ICl2]) is much more soluble in hydrochloric acid. Furthermore, other metal impurities do not form dichloroiodate salts. Caesium dichloroiodate is notable for containing the linear dichloroiodate anions [ICl2]−, with connectivity Cl-I-Cl, which is analog of triiodide anion [I3]−.