Autoionizing states ofH2andH2−using the complex-scaling method

The complex-scaling method is applied to the study of molecular resonances within the framework of the Born-Oppenheimer approximation. In this procedure only the electronic coordinates of the Born-Oppenheimer Hamiltonian are scaled, and thus only the electron-nuclear attraction integrals need be recalculated with explicit complex arguments for each value of the scaling parameter. This method is applied to the study of resonances of ${\mathrm{H}}_2$ and ${\mathrm{H}}_2^{-}$. This represents the first successful application of a complexscaling procedure to the study of a molecular resonance.