Laser-Excited Fluorescence Studies of IR Multiple Photon Dissociation Fragments: NH2(2B1) from CH3NH2 and NH3
Laser excited fluorescence has been used to detect ground state NH2 radicals produced by the infrared multiple photon dissociation (MPD) of CH3NH2 and NH3. A pulsed, line tunable CO2 laser was used to dissociate the molecules; the multimode output, typically 4J total energy, was focussed to a spot ~3mm in diameter inside the reaction vessel. A pulsed dye laser beam of slightly larger diameter intersected the CO2 beam spatially at right angles and at a time adjustable with respect to the CO2 pulse. NH2 was detected in a combination of the l11, 212 and 313 rotational levels of the 2B1(0,0,0) ground state by observing fluorescence following laser excitation at 492.55nm.
Unable to display preview. Download preview PDF.