A flexible new analytical representation for the internuclear potential energy of a diatomic molecule is proposed and tested. The new model may be thought of as a generalization of the prototypical Lennard-Jones (2n ,n) function, with the form V(R) = De[1 - (Re/R)ne-β(z)z]2, where z = (R - Re)/(R + Re) is a dimensionless radial distance variable which approaches 1 as R→∞. This form explicitly incorporates the theoretically predicted attractive inverse-power asymptotic behavior V(R) = D - Cn/Rn associated with most potential energy curves. This "modified Lennard-Jones" (MLJ) function is tested against other flexible forms for the potential energy by performing nonlinear least-squares fits both to known numerical potential curves and to spectroscopic line positions.
|Number of pages||9|
|Journal||Journal of Chemical Physics|
|Publication status||Published - 1 Mar 2000|