HIGH RESOLUTION LASER SPECTROSCOPY: OXYGEN-HYDROGEN STRETCH OF HYDROXYLAMINE; INVESTIGATION OF SATURATION STARK POLARIZATION OF NITROGEN DIOXIDE
COLES, MARY ELLEN
Doctor of Philosophy
The OH stretching fundamental ((nu)(,1)) of hydroxylamine has been studied using a computer controlled color center laser spectrometer. Absorption and Stark modulated spectra were obtained in the spectral region 3620 to 3710 cm('-1). The spectra is dominated by many strong perpendicular type Q branches and exhibits both parallel and perpendicular type lines. A large number of lines have been assigned and a nonlinear least squares fit results in ground and excited state constants. The spectrum of hydroxylamine exhibits many small perturbations, presumably caused by interaction of the (nu)(,1) level with combinations of lower energy vibrational modes. A hot band, wherein the (nu)(,9) torsional motion is excited in both the ground and excited state has been identified and assigned. All lines are believed to originate from the trans form of hydroxylamine and no lines confirming the existence of the cis isomer were observed. A commercially available single mode ring dye laser has been computerized and used in the investigation of the effects of applied electric and magnetic fields on the polarization of laser light propagating through a low pressure sample of NO(,2). Stark polarization spectroscopy has been shown to provide a great simplification of the complex visible absorption spectrum and arises largely due to the combination of Stark mixing and Zeeman nonlinear level crossing phenomena.