The chemical formula of thiophosphoryl chloride is PSCl3, and its CAS number is 3982-91-0. It is a colorless, transparent, fuming liquid with a relative density of 1.668, a melting point of -35°C, and a boiling point of 125°C. It is soluble in benzene, carbon disulfide, and carbon tetrachloride. It hydrolyzes slowly in cold water, and reacts and decomposes rapidly in hot water to form hydrogen chloride, hydrogen sulfide, and phosphoric acid. It is volatile, fumes in air, has a pungent odor and strong lachrymatory effect, and is highly hazardous to the eyes and other mucous membranes. It is mainly used as a raw material for the production of high-efficiency, low-toxicity organophosphorus pesticides, and also for the production of organic synthetic phosphorus compounds.