A variational method to treat diffuse states in weakly bound trimers Original Research Article

A variational method based on the use of pair coordinates and distributed Gaussian functions (DGF) is applied to the study of weakly bound triatomic clusters. The approach is particularly well suited to treat very diffuse states as those presented by the 4He3, and by 4He2X systems, with X being also a very weakly bound atomic ‘impurity’. Several statistical properties such as radial and angular distributions, sizes and dominance of triangular configurations for the corresponding bound states are presented and discussed. The special nature of the Efimov effect is also analyzed in detail.