[CPMD-list] wrong velocities in TRAJECTORY?

[Lan-Feng Yuan (lyuan@Princeton.EDU)]

  Hi, dear CPMD users,

  I want to calculate the kinetic energies of each atom to check equipartitioning. The atomic velocites are stored in the TRAJECTORY file. But in doing that, I am surprised to see that many of the velocites are wrong in path integral calculations! For example, it has lines like:

      1        6.82425508971048        9.52450269497126        9.51015987345505        0.00000000000000        0.00000000000000        0.00000
000000000
      1       12.21231276874373        9.33303372434401        9.34606460682084        0.00000000000000        0.00000000000000        0.00000
000000000
      1        6.00617010855165       11.38389016650084        8.59588245596876        0.00000000000000        0.00000000000000        0.00000
000000000
      1        6.13293595832137        8.15809729569046        8.91367284452267        0.00000000000000        0.00000000000000        0.00000
000000000
      1       10.10949129407331        9.84789884632727        9.34621236955664        0.00000000000000        0.00000000000000        0.00000
000000000
      1       13.21957008182102        9.26567361368209       11.23069151637693        0.00000000000000        0.00000000000000        0.00000
000000000

...

   6000        5.53260233231064       10.68899396835529        8.78025724226381        0.00000000000000        0.00000000000000        0.00000
000000000
   6000        5.59725546928881        8.65292224670147       10.21791288576526        0.00000000000000        0.00000000000000        0.00000
000000000
   6000       10.33714449967338       10.39804084083272        9.61533970021246        0.00000000000000        0.00000000000000        0.00000
000000000
   6000       12.35422745525717        9.05625092206057       11.31325603410190        0.00000000000000        0.00000000000000        0.00000
000000000

  Namely, some beads are reported to have zero velocites from the first step to the last step, but this is obviously not so, because we can see that the atomic positions have changed. And when I restart a new calculation from the RESTART files, it began to report non-zero velocites, but still those velocities don't change with steps.

  I do hope this is a small bug only affecting this specific output ... On the other hand, is there any other way to get velocities?

  Thank you very much! Best regards,

  Lan-Feng

----------------------------
Dr. Lan-Feng Yuan,
Postdoctoral Associate,
Department of Chemistry,
Princeton University,
Princeton, NJ 08544, USA
Office Phone: 1-609-258-1834
Fax: 1-609-258-6746
----------------------------