A quantum chemical study for the multichannel reaction PH2Â +Â PH2

The PH2 + PH2 multichannel reaction path was proposed in this study. The transition state that connects the reactants to cis-P2H2 isomer was found for the first time ever. This process is not allowed to occur at ordinary conditions because of its high energy barrier, 70 kcal mol−1. The PH2 + PH2 disproportionation to form the triplet PH3 radical is an exothermic and spontaneous reaction. The PH2 + PH2 reaction may also form the P2H4 molecule in the absence of surfaces.