What is "chromyl chloride"

n. (context inorganic compound English) The compound CrO₂Cl₂ that is used as an oxidizing agent

Chromyl chloride is a chemical compound with the formula CrOCl. This compound is an opaque dark blood-red liquid at room temperature and pressure. It is tetrahedral, somewhat like SOCl. CrOCl is similar to the most commonly encountered chromium(VI) derivative chromate, [CrO]; both are tetrahedral Cr(VI) compounds. However, they differ in both oxidizing power and in physical properties: one is a liquid and the other forms salts.

CrOCl is a neutral molecular species. This means that in the liquid and solid forms, the individual CrOCl entities interact predominantly via van der Waals bonding. Such weak bonding leads to low melting and boiling points, which is related to the fact that it is a distillable liquid.

The diminished oxidizing power of [CrO] vs. CrOCl can be ascribed to its anionic nature, which diminishes its electron affinity. Also, chloride is a poorer pi-donor ligand than is oxide.