In 1961, John C.Polanyi was the first to point out the possibility of chemical pumping based on vibrational excitation. He proposed four possible reactions, one of which was the reaction of H + Cl. Using an infrared spectrometer, Jerome Kasper and Pimentel discovered infrared pulses produced by photodissociation of iodine, the first chemical laser. In September 1964, they announced their discovery at the first conference on chemical lasers, by that time more than 100 possible chemical reactions and 60 photodissociation reactions were proposed capable of producing laser radiation. However, at the symposium in San Diego only one working laser was reported, which was laced with photodissociation of iodine. In 1965, Kasper and Pimentel discovered the laser radiation HCl, arising from the explosion of the system H / Cl. After the discovery of the laser based on the reaction of F + H in 1967, the number of chemical lasers found by the Pimentel laboratory rapidly increased. Thus, Pimentel first transformed the chemical energy obtained as a result of vibrational excitation into laser radiation.