Gmx select to get index of upper and lower leaflet residues in bilayer

[alevilla]

Hi

I think it is possible to create a index group for upper and slower leaflet using z as reference. But maybe that some rethinking on the order of the definition is needed ( Here is selection syntax https://manual.gromacs.org/current/onlinehelp/selections.html?highlight=selection).

Maybe this conversation is useful

Gmx select

GROMACS version: 2020.1 GROMACS modification: No I have a lamellar system consisting of four bilayers. After the equilibration run, the bilayers get diffused. So now I want to split each bilayer and do a separate analysis. For separating each bilayer I am using gmx select tool, but every time it is giving me a syntax error. Like I have tried - “group 0 30 < z < 40” and also “resname PPG within 40 of PPT” and then “group 0 z > 30 & z < 40”. But none of the selection criteria is working. All of …

\Alessandra