Collisional deactivation of PH2((A)over-tilde2A1; V;′2=1,0) and PH2((X)over-tilde2B1;V;"2=1) by some triatomic molecules

The deactivation constants of PH2((A) over tilde (2)A(1); upsilon'(2) = 1,0) and PH2((X) over tilde B-2(1) : upsilon"(2) = 1) which are due to collisions with CO2, N2O, and SO2 have been measured. Comparisons with data due to rare gas and diatomic quenchers have shown that the electronically excited PH2 species are probably quenched by multiple channel mechanisms of both physical and chemical nature for SO2 and of prevalently physical nature for CO2 and N2O. A V-V energy transfer is clearly responsible for the vibrational relaxation of PH2((X) over tilde B-2(1) : upsilon"(2) = 1) by these triatomic quenchers.