[ase-users] Changes to implementation details (files) in Vibrations/Phonons

[Ask Hjorth Larsen]

Dear all,

For security, Vibrations and Phonons modules will use JSON in the
future instead of pickle.  Indeed all features that used pickle for
storage now use JSON instead.

This requires porting the old picklefiles if you rely on "restarting"
in order to read calculated results, and there will be a tool for
doing that -- at least for the most common cases.

Also if you have workflows or programs that depend directly on the
picklefiles, then those will almost certainly break.  If all things
were ideal we would have a deprecation period where both new and old
behaviour is supported.  But things are not ideal and we won't have a
deprecation period unless someone else kindly implements it.

In conclusion:  If your software works directly with the pickle files
from Vibrations or Phonons, then it's wise to ensure that things work
with current ASE master.

Best regards
Ask