Recovery of the long range potential in BeAr+ by potential inversion methods

The results of the potential inversion methods of Dunham, Simons, Parr, and Finlan, Thakkar, Huffaker, and the Padé approximate technique are presented for the X 2Σ+ state of BeAr+. The method of Thakker is shown to yield reasonable behavior at long range, leading to an ion-induced dipole interaction. A simple model potential is shown to provide a good description of the bonding in both the ground state and the A 2Πr state. The effective nuclear charge of Be+ is found to be 1.29 in the X state and 1.88 in the A state. Integration of the various potentials to determine the vibrational eigenvalues shows the superiority of the Thakkar and Huffaker methods and shows the three parameter model potential to be a very good representation of the true potential.