In this study, simulated flame and combustion processes were initiated by multiple-photon absorption from high power infrared (IR) laser sources. Subsequent examination of the system was performed by dye laser induced fluorescence (LIF), multiphoton spectroscopy, and visible and infrared emission. To understand combustion and flame reaction, a knowledge of the kinetic role of free radicals such as C/sub 3/, CH, C/sub 2/, and OH, is critical. For this reason the reaction dynamics of the C/sub 3/ radical in the presence of O/sub 2/, NO and various hydrocarbons was investigated. The production of C/sub 3/ radicals, vibrational relaxation and chemical kinetics following IR photolysis of allene are discussed.