Geometric phase effects in ${\mathrm{H}}_3$ predissociation

We model the predissociation of ${\mathrm{H}}_3$ in the electronic state corresponding to the upper sheet of the conically intersecting $1{{}^{2}A}^{\prime }$ and $2{{}^{2}A}^{\prime }$ states, and we show that product-state rovibrational distributions are strongly influenced by the geometric phase. Similarly, the differences in the product-state energy distributions in recent three-body dissociation experiments for the $2s,{}^{2}A_1^{\prime }$ and $2p,{}^{2}A_2^{″}$ states of ${\mathrm{H}}_3$ are shown to result from the presence of the geometric phase in this system, and thus provide experimental evidence of the influence of this phase in a molecular dynamical process.

Figure 1

(Color online) Smith lifetimes for $A_1$ and $A_2$ rovibronic wave functions. The vertical arrows indicate the energies of the bound states on the upper electronic potential energy surface, when coupling to the ground electronic state is neglected.

Figure 2

(Color online) Population of the different $\mathrm{H}+{\mathrm{H}}_2(v,j)$ channels in the decay of the $A_1$ and $A_2$ resonances at 4.41 and $4.49\mathrm{eV}$, respectively.