g_potential

Main Table of Contents

VERSION 4.0_rc1
Mon 22 Sep 2008


Description

Compute the electrostatical potential across the box. The potential iscalculated by first summing the charges per slice and then integratingtwice of this charge distribution. Periodic boundaries are not taken into account. Reference of potential is taken to be the left side ofthe box. It's also possible to calculate the potential in sphericalcoordinates as function of r by calculating a charge distribution inspherical slices and twice integrating them. epsilon_r is taken as 1,2 is more appropriate in many cases

Files

optionfilenametypedescription
-f traj.xtc Input Trajectory: xtc trr trj gro g96 pdb cpt
-n index.ndx Input Index file
-s topol.tpr Input Run input file: tpr tpb tpa
-o potential.xvg Output xvgr/xmgr file
-oc charge.xvg Output xvgr/xmgr file
-of field.xvg Output xvgr/xmgr file

Other options

optiontypedefaultdescription
-[no]h bool no Print help info and quit
-nice int 19 Set the nicelevel
-b time 0 First frame (ps) to read from trajectory
-e time 0 Last frame (ps) to read from trajectory
-dt time 0 Only use frame when t MOD dt = first time (ps)
-[no]w bool no View output xvg, xpm, eps and pdb files
-[no]xvgr bool yes Add specific codes (legends etc.) in the output xvg files for the xmgrace program
-d string Z Take the normal on the membrane in direction X, Y or Z.
-sl int 10 Calculate potential as function of boxlength, dividing the box in #nr slices.
-cb int 0 Discard first #nr slices of box for integration
-ce int 0 Discard last #nr slices of box for integration
-tz real 0 Translate all coordinates <distance> in the direction of the box
-[no]spherical bool no Calculate spherical thingie
-ng int 1 Number of groups to consider
-[no]correct bool no Assume net zero charge of groups to improve accuracy

Known problems


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