1 .TH g_density 1 "Mon 4 Apr 2011" "" "GROMACS suite, VERSION 4.5.4-dev-20110404-bc5695c"
3 g_density - calculates the density of the system
5 .B VERSION 4.5.4-dev-20110404-bc5695c
9 .BI "\-n" " index.ndx "
10 .BI "\-s" " topol.tpr "
11 .BI "\-ei" " electrons.dat "
12 .BI "\-o" " density.xvg "
14 .BI "\-[no]version" ""
28 \&Compute partial densities across the box, using an index file.
31 \&For the total density of NPT simulations, use \fB g_energy\fR instead.
35 \&Densities are in kg/m3, and number densities or electron densities can also be
36 \&calculated. For electron densities, a file describing the number of
37 \&electrons for each type of atom should be provided using \fB \-ei\fR.
38 \&It should look like:
42 \& \fB atomname = nrelectrons\fR
44 \& \fB atomname = nrelectrons\fR
46 \&The first line contains the number of lines to read from the file.
47 \&There should be one line for each unique atom name in your system.
48 \&The number of electrons for each atom is modified by its atomic
53 Trajectory: xtc trr trj gro g96 pdb cpt
55 .BI "\-n" " index.ndx"
59 .BI "\-s" " topol.tpr"
61 Run input file: tpr tpb tpa
63 .BI "\-ei" " electrons.dat"
67 .BI "\-o" " density.xvg"
73 Print help info and quit
75 .BI "\-[no]version" "no "
76 Print version info and quit
78 .BI "\-nice" " int" " 19"
81 .BI "\-b" " time" " 0 "
82 First frame (ps) to read from trajectory
84 .BI "\-e" " time" " 0 "
85 Last frame (ps) to read from trajectory
87 .BI "\-dt" " time" " 0 "
88 Only use frame when t MOD dt = first time (ps)
91 View output \fB .xvg\fR, \fB .xpm\fR, \fB .eps\fR and \fB .pdb\fR files
93 .BI "\-xvg" " enum" " xmgrace"
94 xvg plot formatting: \fB xmgrace\fR, \fB xmgr\fR or \fB none\fR
96 .BI "\-d" " string" " Z"
97 Take the normal on the membrane in direction X, Y or Z.
99 .BI "\-sl" " int" " 50"
100 Divide the box in nr slices.
102 .BI "\-dens" " enum" " mass"
103 Density: \fB mass\fR, \fB number\fR, \fB charge\fR or \fB electron\fR
105 .BI "\-ng" " int" " 1"
106 Number of groups to compute densities of
108 .BI "\-[no]symm" "no "
109 Symmetrize the density along the axis, with respect to the center. Useful for bilayers.
111 .BI "\-[no]center" "no "
112 Shift the center of mass along the axis to zero. This means if your axis is Z and your box is bX, bY, bZ, the center of mass will be at bX/2, bY/2, 0.
115 \- When calculating electron densities, atomnames are used instead of types. This is bad.
120 More information about \fBGROMACS\fR is available at <\fIhttp://www.gromacs.org/\fR>.