The dynamics of the C + PH3 reaction: a theoretical study

The C + PH(3) reaction is one of the simplest gas-phase processes which can produce molecular species containing P-C bonds. It could be of astrophysical importance and a reference for other phosphine reactions with carbon-containing molecular radicals. The dynamical aspects have been studied theoretically by quasi-classical trajectory methods in order to determine its rate as a function of the temperature, the branching ratios, and the molecular mechanisms. We have obtained a T(0.2) dependence of the capture rate. The total rate is affected by the existence of relatively high-lying saddle points for the isomerization of the CPH(3) complex but get a value of 0.82·10(-10) cm(3) s(-1) at 300 K, which is considered quite high for a neutral-neutral reaction and higher than those of similar reactions. Moreover, the total rate presents a weak dependence with the temperature. Our results indicate that several products containing P-C bonds are formed, the main reaction channel being the generation of HPCH + H.