Collect. Czech. Chem. Commun. 2003, 68, 1-22

The 4He Trimer: Structure and Energetics of a Very Unusual Molecule

Cono Di Paolaa, Franco A. Gianturcoa,*, Gerardo Delgado-Barriob, Salvador Miret-Artésb and Pablo Villarrealb

a Department of Chemistry, The University of Rome, Cittá Universitaria, 00185 Rome, Italy
b Instituto de Mátematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 123, 28006 Madrid, Spain


The 4He3 weakly interacting system is analysed by constructing the full interaction as a sum of two-body (2B) potentials chosen among the most recent proposals from the literature. The spatial density distributions of the three bound atoms are obtained using a diffusion Monte Carlo (DMC) algorithm and a stochastic analysis under specific geometric constraints is carried out with the resulting densities in order to recover a more conventional structural picture for such floppy system. The total binding energies were obtained with the chosen potentials analysed in the present work, using the DMC algorithm, and are compared with previous published results. The ensuing spatial distributions are analysed in some detail to select the dominant structures from a conventional triangular description of this very floppy molecule.

Keywords: Helium clusters; Two-body interaction potentials; Diffusion Monte Carlo algorithm; Stochastic analysis; Quantum chemistry; Ab initio calculations.

References: 40 live references.