Raman spectra of I4O9 formed by the reaction of iodine with ozone

The Raman spectrum of I4O9, formed by the gas‐phase reaction of I2 with O3, has been measured. Freshly prepared samples of I4O9 gave broad band spectra characteristic of an amorphous solid. Vibration bands at 780, 740, 620 and 450 cm−1 were observed. It was established conclusively that I4O9 is a distinct molecular species and not a mixture of I2O5 and I2O4.