MASS SCALING IN THE MOLECULAR APPROACH - DIRECT CORRELATION AMONG VIBRATIONAL H-2(-LEVELS() AND ELECTRONIC HE ENERGY)

The molecular approach to ABA Coulomb systems is successfully extended to atomic systems. Adiabatic and nonadiabatic energies of some low-ly ing J = 0 bound states of the helium atom are calculated. These energy levels are directly related to vibrational levels of the hydrogen mol ecular ion in a correlation diagram, a procedure that is equivalent to mass scaling, relative to the mass ratio lambda = m(A)/m(B), of the a diabatic and nonadiabatic wavefunction, that has the same analytical f orm for all lambda.