Laser-induced photodestruction of the organo-phosphates: DIMP and DMMP

The infrared and ultraviolet laser-induced photodestruction of diisopropyl methylphosphonate (DIMP) and dimethyl methylphosphonate (DMMP) has been surveyed. We used the excimer lasers ArF (193 nm), KrF (248 nm), XeCl (308 nm), and quadrupled Nd:YAG (266 nm) as well as a pulsed CO2 laser. Samples were irradiated in the vapor and liquid phases. Photodissociation was observed at all irradiation wavelengths, being most efficient when ArF irradiated DIMP or DMMP in the vapor phase in the presence of air or oxygen. Pulsed, focused CO2 radiation led to multiple photon dissociation and pyrolytic destruction. Light hydrocarbon gases were the principal decomposition products. Hydrogen, CO, CO2 and water were also detected. The residual liquid is likely to be a phosphorus-bearing acid.