Hi Thomas,


I noticed a few things:

- when I run "supercell 2, 1, 1" I get another cell outline along the a axis, but no atoms are shown in the second cell. Do I have to run another command for them to show up?
- when I run the command again with other values for a, b, or c, nothing changes. I would expect that running the sequence "supercell 2, 1, 1" and then "supercell 2, 2, 1" would show me a 2x2x1 supercell at the end, but I see only the 2x1x1 supercell.

Thanks again,


On Wed, Apr 14, 2010 at 03:24, Thomas Holder <thomas@thomas-holder.de> wrote:
Hi Nick,

I recently was playing with (aka learning) the crystallographic symmetry
information in PDB files and now took your feature request as an
exercise. See attached file, hope it does what you had in mind.


On Mon, 2010-04-12 at 14:12 -0600, Nicolas Bock wrote:
> It would be great if pymol had support for constructing and displaying
> a supercell:
> For data files that support crystallographic information, e.g. pdb,
> pymol can already display the unit cell (show cell). It would be great
> if one could easily display multiple copies of the unit cell, along
> the lines of
> supercell 1,1,2
> where pymol would then copy the unit cell along the c-axis and display
> 2 unit cells.
> supercell 2,2,2
> would display 2 copies along the a, b, and c axes, and display 8 unit
> cells in total.
> As a related request it would be great if pymol could construct a unit
> cell in case the crystallographic information in the input file does
> not exist. This could come in handy for instance when reading from
> xyz. Maybe a command such as
> construct_supercell a=10.2, b=10.2, c=15, alpha=90.0, beta=90,
> gamma=90
> would construct a cubic cell with dimensions axbxc.
> Thanks,
> nick