Abstract

Semi-empirical potential energy surfaces for alkali-trimers are derived from the simplest form of London's approximation, by evaluating the Coulomb and exchange integrals as half of the sum and difference of two new interaction potential curves for the 1 2g + and 3 J?u + states of the cor-responding alkali dimers. The trimers attain maximum stability in their linear symmetric con-figuration. The force constants corresponding to stretching and bending deformations of the homo-nuclear trimers have been calculated for the linear symmetric configuration. Unlike the stretching, the bending deformation is seen to be very much insensitive to the ground state energy variation of the trimers.