Thanks a lot, Elaine, this worked indeed!
Just one final point: how can I make the linewidth larger? When I make a picture, the thin lines of the box disappear.
I understand ChimeraX interpretes these lines as a surface, I can change the colour when choosing surface in the colour blow up.

On 18/11/22 17:49, Elaine Meng wrote:
Hi Xavier,
As far as I can tell, it is exactly the same in ChimeraX as in Chimera.  First, make sure you aren't using a very old version of ChimeraX.  I tried it in ChimeraX 1.5 release candidate (2022-11-08)  just now:

- open your structure that has unit cell information, e.g. 1fav

- in Unit Cell tool (menu: Tools... Higher-Order Structure... Unit Cell) click Outline to show unit cell box

- if you want to change box outline color, can use the same method as described below for Chimera. I wasn't able to select it by Ctrl-click, however, so instead use the selection (hand with green dot) checkbox in the Model Panel to select it, then use Actions... Color... [...].    Or, you can just click the color square in the Model Panel and use the system color chooser to change the color interactively.   Screenshot:



I hope this helps,
Elaine
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Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco

P.S. for ChimeraX questions specifically, you may want to use the other mailing list, chimerax-users@cgl.ucsf.edu 

On Nov 18, 2022, at 7:03 AM, F.Xavier Gomis-Rüth via Chimera-users <chimera-users@cgl.ucsf.edu> wrote:

Dear Elaine,
I am now trying to get this done in ChimeraX where there is indeed a similar option. Unfortunately, if I proceed as in the instructions
I do not get the cell box, in contrast with old Chimera. I also tried through the command line but unsuccessfully.
Am I missing something?
Thanks a lot in advance,
Xavier

On 26/10/22 17:45, Elaine Meng wrote:
Hi Xavier,
You can select the box (Ctrl-click on it) and then use menu: Actions... Color... [choose color], then clear selection by Ctrl-click on blank area of window or menu Select... Clear Selection.
I hope this helps,
Elaine
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Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco


On Oct 26, 2022, at 1:56 AM, F.Xavier Gomis-Rüth via Chimera-users <chimera-users@cgl.ucsf.edu>
 wrote:

Dear all,
is there a way in Chimera or ChimeraX to get the unit-cell box being drawn in another colour than white?
This forces the background to be dark....
Thanks a lot in advance,
Xavier




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