The Infrared Spectrum of Chlorine Dioxide

Abstract

The infrared spectrum of ClO2has been reinvestigated from 2–40μ. Several new bands have been discovered, among them the bending frequency ν2 at 445 cm−1. This band has the doublet character required if the molecular model is to be an obtuse triangle in accord with electron diffraction experiments. Three bands, ν1, ν2, and 2ν1, were resolved with prism and grating methods, and the spacing of the Q lines was found to be about 3.0 cm−1. An A″—B″ value of 1.413 cm−1 was obtained from the analysis of ν2, and this value also is in excellent agreement with the electron diffraction measurements. Moments of inertia computed from the r(Cl–O) = 1.49A and 2α (apex angle) = 118.5° obtained from a combination of electron diffraction and infrared data are IA=16.09×10−40 g cm2, IB=86.35×10−40 g cm2, and IC=102.43×10−40 g cm2. A band which cannot be ascribed to an impurity was found at 290 cm−1. The possibility that this band results from polymerization of ClO2 is suggested.