Variational theory for the ground state of linear E-e Jahn-Teller system: Weak- and intermediate-coupling

Abstract

We present a simple variational treatment for the ground state of the linear E-e Jahn-Teller system. We have argued that the proposed ground state wavefunction is valid for the weak- and intermediate-coupling case, where the dynamical effect, the nonadiabaticity is the most important one. Both the variational estimates of ground state energy and the calculation of Ham's reduction factor have shown that our results are not only in good agreement with the results of exact diagonalization, but also they are better than those of the previous analytical studies. We have discussed the physical meaning of the proposed wavefunctions.