Dear ASE developers,
I’m running some normal mode calculations and have a question about the argument delta
in the Vibrations
class. According to the documentation, it represents the magnitude of displacements. With nfree = 2
, each atom is displaced by -delta
and +delta
along each Cartesian coordinate. I’ve tested different values of delta and noticed that while the geometries saved in the .traj files remain the same, the order in which they are saved changes. I also subtracted the positions of the images from the reference structure, but the differences were never a multiple of the delta I selected. Are these results expected? What is the effect of varying delta, and how can I evaluate its impact? Also, what parameter does ASE use to determine the extent of vibrations, i.e., the maximum and minimum positions?
Yours sincerely,