Checking the influence of numerically induced chaos in the computational study of intramolecular dynamics using trajectory equivalence

Influence of the numerical chaos induced by the numerical round-off errors in the classical trajectory study of intramolecular dynamics has been investigated using HOD as an example. Calculation of the trajectory equivalence based on the scaling theorem for classical dynamics has been found useful to check the onset of the numerically induced chaos. It has also been found that the use of higher precision arithmetic is not very effective to delay this onset.