DISPERSION STABILIZATION OF SOLVATED ELECTRONS AND DIPOLE-BOUND ANIONS

It has long been assumed that stability of ''solvated electrons'' and dipole-bound anions results primarily from the static Coulomb interact ion of an excess electron with charge distribution of the neutral mole cular host. Our results indicate, however, that the dispersion interac tion between the loosely bound electron and the neutral molecular host is as important as the static Coulomb stabilization. A perturbation s cheme is designed to analyze physically meaningful components of elect ron binding energy, and highly correlated electronic structure results are presented for dipole-bound anions and solvated electrons in the ( HF)(n) clusters (n = 2, 3). The vertical electron detachment energy fo r (HF)(3)(-) was found to be 0.63 and 0.21 eV for the solvated electro n and dipole-bound anion, respectively. The equilibrium zigzag geometr ical structure of the dipole-bound anion differs drastically from the cyclic C-3h structure of the neutral trimer.