title: Theoretical modeling of ionization energies of argon clusters: nuclear delocalization effects.
abstract: Temperature dependence of vertical ionization energies is modeled for small argon clusters (N ≤ 13) using classical parallel-tempering Monte Carlo methods and extended interaction models based on the diatomics-in-molecules approach. Quantum effects at the zero temperature are also discussed in terms of zero-point nuclear vibrations, either at the harmonic approximation level or at the fully anharmonic level using the diffusion Monte Carlo calculations. Both approaches lead to a considerable improvement of the theoretical predictions of argon clusters ionization energies and represent a realistic way of modeling of ionization energies for weakly bound and floppy complexes in general. A thorough comparison with a recent electron-impact experiment [O. Echt et al., J. Chem. Phys. 123, 084313 (2005)] is presented and a novel interpretation of the experimental data is proposed.
authors.affiliation: Department of Physics, University of Ostrava, 30. dubna 22, 701 03 Ostrava, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Svrčková
authors.forename: Aleš
authors.initials: A
authors.lastname: Vítek
authors.forename: František
authors.initials: F
authors.lastname: Karlický
authors.forename: Ivana
authors.initials: I
authors.lastname: Paidarová
authors.forename: René
authors.initials: R
authors.lastname: Kalus