Hi Caleb, Unit Cell uses specific information about crystallographic and noncrystallographic symmetries that are included in PDB files. Trajectory formats don't have that specific information, so Unit Cell can't build the repeating units. The MD Movie playback tool also does not have any capability for automatically extending the system through periodic boundaries, sorry. Best, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

On Oct 5, 2022, at 6:18 PM, Huang, Caleb via Chimera-users <chimera-users@cgl.ucsf.edu> wrote:

Hello,

I'm trying to make a psf+dcd movie with periodic boundaries on. The feature I'm looking for I believe is "Unit Cell", but it seems to only work for pdb files. Is there a way to create repeating cells using psf+dcd files?

Thanks for any help! -Caleb