Delta function model for the helium trimer: origin of three-body forces |
| |
Authors: | S. M. BLINDER LAWRENCE L. LOHR |
| |
Affiliation: | Department of Chemistry , University of Michigan , Ann Arbor, MI, 48109-1055, USA |
| |
Abstract: | The Dirac bubble potential, previously used to model the helium dimer, is applied to the trimer. It is shown that the quantum mechanical kinetic energy operator for a three-body system contains terms over and above the analogues of classical pairwise contributions. The additional terms, the ‘Borromean couplings’, are responsible for a dramatic increase in the binding energy of the trimer. For example, 4He3 is bounded by two orders of magnitude more strongly than 4He2, 279 mK versus 1.31 mK, respectively, according to our calculations. Moreover, the trimer is considerably more compact than the dimer, with (r12) decreasing to 9.01 Å from 51.9 Å. |
| |
Keywords: | Lindqvist-type polyanions electronic structures redox properties density functional theory |
|
|