Simultaneous observation of dipole-bound and valence electron states in pyridine tetramer anion.

Examines the coexistence of dipole-bound and valence electron states using photoelectron spectroscopy in pyridine tetramer anion. Difference of states in polarization dependence; Analysis on numerous cases of dipole-bound electrons in cluster system; Thermodynamic stability of the dipole-bound and valence electron.