Experimental and theoretical study of the atmospherically important O2-H2O complex.

The theoretically predicted water-oxygen van der Waals adduct has been experimentally confirmed by vibrational characterization using matrix isolation spectroscopic studies at 10 K. Vibrational bands for asymmetric and symmetric OH-stretching for this adduct have been found at 3728 cm(-1) and 3639 cm(-1), respectively. Theoretical calculations performed with Gaussian 98 software at the MP2/6-311++G(2d,2p) level of theory support the alternative structure of the hydrated complex proposed by this study.

Fourier transform infrared-probed O(3P) microreactor: demonstration with ethylene reactions in argon matrix.

To demonstrate the development of an oxygen atom microreactor in the form of liquid-helium-cooled solid argon matrix deposited on an infrared (IR) window, the oxidation of ethylene by mobile O atoms has been investigated. O atom diffusion through the argon matrix is confirmed and used to examine ethylene-oxygen atom reactions. In a bench-scale matrix isolation system probed with a Fourier transform infrared (FT-IR) spectrometer, matrices of solid Ar at 8-10 K doped with NO2 and ethylene have been prepared on a ZnSe window within an evacuated cryostat.

Water-related matrix isolation phenomena during NO2 photolysis in argon matrix.

Photolysis (350-450 nm) of NO(2) molecules trapped in argon matrices at 10 K has been studied using Fourier transform infrared (FTIR) spectroscopy to examine the mobility of the photolysis products, O((3)P) and NO, and their subsequent reactions. The formation of N(2)O(5) and N(2)O(3) from reactions of these mobile species with immobilized NO(2) and N(2)O(4) is confirmed. Water molecules from the background gases in the vacuum have been found to be isolated in the argon matrix during deposition of diluted NO(2) in Ar.