Infrared spectrum of carbon dioxide in aqueous solution

Abstract We have studied the infrared absorption band due to the antisymmetric stretching fundamental, ν 3 , of carbon dioxide in water at 2342.9 cm −1 for 12 CO 2 and 2277.7 cm −1 for 13 CO 2 , from the point of view of structural and analytical chemistry. The position of this band is shifted by only 6 cm −1 from the vapour value, indicating the absence of hydrogen bonding between water molecules and the dissolved carbon dioxide. The ν 3 band has good analytical potential and may be used for the determination of carbon dioxide in water. We have also examined the analytical use of the infrared bands of aqueous carbonate and bicarbonate ions.