Observation of nu1+nu(n) combination bands of the HOOO and DOOO radicals using infrared action spectroscopy.
Hydrogen trioxy (HOOO) and its deuterated analog (DOOO) have been generated in a supersonic free-jet expansion through association of photolytically generated OH or OD and molecular oxygen. The radicals were detected using infrared action spectroscopy, a highly sensitive double resonance technique. Rotationally resolved spectra of combination bands of HOOO and DOOO comprising one quantum of OH or OD stretch (nu(1)) and one quantum of a lower frequency mode (nu(1)+nu(n) where n=3-6), including HDOO bend (nu(3)), OOO bend (nu(4)), central OO stretch (nu(5)), and HDOOO torsion (nu(6)), have been observed and assigned to the trans conformer. All but one of these bands are accompanied by unstructured features which are tentatively assigned to the corresponding vibration of the cis conformer. In total, five additional bands of HOOO and four of DOOO have been recorded and assigned. These data represent the first gas-phase observation of the low-frequency modes of HOOO and DOOO and they are found to differ significantly from previous matrix studies and theoretical predictions. Accurate knowledge of the vibrational frequencies is crucial in assessing thermochemical properties of HOOO and present possible means of detection in the atmosphere.
Derro
Erika L
EL
Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
Sechler
Timothy D
TD
Murray
Craig
C
Lester
Marsha I
MI
D003903:Deuterium; D017665:Hydroxyl Radical / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014732:Vibration
D017665:Hydroxyl Radical; D003903:Deuterium; D010100:Oxygen