On the adiabatic and nonadiabatic corrections in the ground electronic state of the hydrogen molecular cation

Adiabatic and non-adiabatic corrections to the dissociation energies of the hydrogen molecular cations, H-2(+) and D-2(+), are considered in a study to investigate whether they can be calculated approximately by using scaling factors for the potential and reduced masses for the vibrational and rotational motion. It is concluded that only the potential should be modified to allow for adiabatic effects. For non-adiabatic corrections the use of a vibrational reduced mass close to that calculated using atomic masses is recommended, but there is not a strong case for changing the rotational reduced mass from that determined using nuclear masses.