Improved adiabatic calculations of the vibrational-rotational states ofHD+

Potential curves have been calculated for the ground electronic state of ${\mathrm{HD}}^{+}$ within the framework of an improved adiabatic approximation. Both the J=0 and J=1 rotational states have been examined in detail using the new approach. This formulation takes into account the symmetry-breaking effects due to the unequal masses of the two nuclei, in contrast to the standard adiabatic approximation. The technique is found to yield significant improvement over the standard adiabatic approach for the highly excited vibrational states of ${\mathrm{HD}}^{+}$.