Long-range damping functions improve the short-range behaviour of 'MLR' potential energy functions
Abstract
The recently introduced [Mol. Phys. 105, 663 (2007)] 'Morse/long-range' (or MLR) potential energy function is a very flexible form which explicitly incorporates the theoretically predicted inverse-power-sum long-range tail, is smooth and differentiable everywhere, and includes the well depth ? , equilibrium distance r e, and long-range interaction coefficients Cm as explicit parameters. This form is being used increasingly commonly in direct-potential-fit analyses of experimental data. The present work shows that the MLR form can readily accommodate the inclusion of 'damping functions' in the description of the long-range potential tail, and that inclusion of such terms leads to much more realistic short-range extrapolation behaviour. Illustrative applications to the ground electronic states of MgH, Li2 and ArXe are presented.
- Publication:
-
Molecular Physics
- Pub Date:
- February 2011
- DOI:
- 10.1080/00268976.2010.527304
- Bibcode:
- 2011MolPh.109..435L
- Keywords:
-
- potential energy function;
- damping functions;
- MgH;
- Li<SUB>2</SUB>(X);
- ArXe