Modify box info for a loaded topology

parmbox [parm <name> | parmindex <#> | <#>] [nobox] [truncoct] [x <xval>] [y <yval>] [z <zval>] [alpha <a>] [beta <b>] [gamma <g>]

[parm <name> | parmindex <#> | <#>] Name/tag or index of topology to modify. Default is first loaded topology.
[nobox] Remove box information.
[truncoct] Set truncated octahedon angles with lengths equal to <xval>.
[x <xval>] Box X length.
[y <yval>] Box Y length.
[z <zval>] Box Z length.
[alpha <a>] Box alpha angle.
[beta <b>] Box beta angle.
[gamma <g>] Box gamma angle.

Modify the box information for specified topology. Overwrites any box information if present with specified values; any that are not specified will remain unchanged. Note that unlike the box action this command affect box information immediately. This can be useful for e.g. removing box information from a parm when stripping solvent:

parm mol.water.parm7
parmstrip :WAT
parmbox nobox
parmwrite out strip.mol.nobox.parm7