https://doi.org/10.1140/epjd/e2002-00211-3
Charged cores in ionized 4He clusters
I: The He2+···He system
1
Department of Chemistry and INFM, University of Rome “La
Sapienza”, Piazzale A. Moro 5, 00185 Rome, Italy
2
Dipartimento di Chimica e Chimica Industriale, University of Genoa, via Dodecaneso 31, 16146 Genoa, Italy
Corresponding author: a fa.gianturco@caspur.it
Received:
25
June
2002
Revised:
27
August
2002
Published online:
22
October
2002
Experimental and theoretical studies in large ionic helium clusters
have suggested the presence of a diatomic (and occasionally triatomic)
charged molecular core surrounded by the other atoms which are bound
to it by weaker interactions [CITE]. The understanding
of the interactions between the system He
and an additional
He atom of the cluster is therefore important in order to start
modelling the full cluster interaction potential. In the present work
we carry out a new set of calculations on the full potential and on
the bound states supported by the He isolated ion and
further extend them to generate a Rigid Rotor (RR) potential energy
surface (PES) for the triatomic system with He kept
at its equilibrium geometry (2.0 a.u.). The 13 bound states which
were found and the overall angular anisotropy that exists for this
Potential Energy Surface (PES) are discussed in detail. We additionally
show results of calculations on the surface vibrational extension
to nine different values of the He interatomic distance,
thereby generating a fuller, three-dimensional interaction potential.
A simpler modelling of the latter via “Pseudo Rigid Rotor” calculations
for the bound states with a vibrationally excited core is also presented
and discussed.
PACS: 36.40.Wa – Charged clusters / 31.50.Gh – Surface crossings, non-adiabatic couplings / 31.50.Bc – Potential energy surfaces for ground electronic states / 31.15.Ar – Ab initio calculations
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002
