FeI3, or iron(III) iodide, is a chemical compound composed of iron and iodine. It has the formula FeI3, indicating that each molecule contains one iron atom and three iodine atoms. This compound typically appears as a dark brown or black solid and is known for its use in various chemical reactions and applications in organic synthesis. In terms of its properties, FeI3 is soluble in organic solvents but less so in water. It can act as a Lewis acid, meaning it can accept electron pairs from other substances during chemical reactions. This characteristic makes it valuable in coordination chemistry and catalysis.