THE ABSORPTION OF PULSED CO2-LASER RADIATION BY METHYLPHOSPHINE AS A FUNCTION OF WAVE-NUMBER, FLUENCE, PULSE DURATION, TEMPERATURE, OPTICAL-PATH LENGTH AND PRESSURE OF ABSORBING AND NONABSORBING GASES

The absorption of four lines (P12 (951.2 cm(-1)) and R22 (977.2 cm(-1) ) (00 degrees 1-10 degrees 0 transition) and P36 (1031.5 cm(-1)) and R 20 (1078.6 (cm(-1)) (00 degrees 1-02 degrees 0 transition) of a pulsed CO2 laser by CH3PH2 was examined at various pulse energies, pulse dur ations, temperatures, optical path lengths and pressures of the compou nd and non-absorbing foreign gases. In addition, the low intensity IR absorption spectrum of methylphosphine was compared with high intensit y absorption data relevant to all lines of the pulsed CO, laser. The e xperimental characteristics demonstrate non-linear features of the abs orption phenomena and can be expressed analytically by a formula equiv alent to an extended form of the phenomenological Beer-Lambert law. Th e importance of the results obtained for revealing general regularitie s governing the multiphoton absorption and the potential applications of CH3PH2 are indicated briefly.