2 research outputs found
Rydberg-London Potential for Diatomic Molecules and Unbonded Atom Pairs
We propose and test a pair potential that is accurate at all relevant
distances and simple enough for use in large-scale computer simulations. A
combination of the Rydberg potential from spectroscopy and the London
inverse-sixth-power energy, the proposed form fits spectroscopically determined
potentials better than the Morse, Varnshi, and Hulburt-Hirschfelder potentials
and much better than the Lennard-Jones and harmonic potentials. At long
distances, it goes smoothly to the correct London force appropriate for gases
and preserves van der Waals's "continuity of the gas and liquid states," which
is routinely violated by coefficients assigned to the Lennard-Jones 6-12 form.Comment: Five pages, 10 figure
Parametrization of the Hybrid Potential for Pairs of Neutral Atoms
The hybrid form is a combination of the Rydberg potential and the London
inverse-sixth-power energy. It is accurate at all relevant distance scales and
simple enough for use in all-atom simulations of biomolecules. One may compute
the parameters of the hybrid potential for the ground state of a pair of
neutral atoms from their internuclear separation, the depth and curvature of
their potential at its minimum, and from their van der Waals coefficient of
dispersion.Comment: 7 pages, 11 figures, includes lithium, sodium, & potassium dimers,
minor correction