1GMX-DYECOUPL(1) GROMACS GMX-DYECOUPL(1)
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6 gmx-dyecoupl - Extract dye dynamics from trajectories
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9 gmx dyecoupl [-f [<.xtc/.trr/...>]] [-n [<.ndx>]] [-ot [<.xvg>]]
10 [-oe [<.xvg>]] [-o [<.dat>]] [-rhist [<.xvg>]]
11 [-khist [<.xvg>]] [-b <time>] [-e <time>] [-tu <enum>]
12 [-[no]w] [-xvg <enum>] [-[no]pbcdist] [-[no]norm]
13 [-bins <int>] [-R0 <real>]
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16 gmx dyecoupl extracts dye dynamics from trajectory files. Currently, R
17 and kappa^2 between dyes is extracted for (F)RET simulations with
18 assumed dipolar coupling as in the Foerster equation. It further
19 allows the calculation of R(t) and kappa^2(t), R and kappa^2 histograms
20 and averages, as well as the instantaneous FRET efficiency E(t) for a
21 specified Foerster radius R_0 (switch -R0). The input dyes have to be
22 whole (see res and mol pbc options in trjconv). The dye transition
23 dipole moment has to be defined by at least a single atom pair, however
24 multiple atom pairs can be provided in the index file. The distance R
25 is calculated on the basis of the COMs of the given atom pairs. The
26 -pbcdist option calculates distances to the nearest periodic image
27 instead to the distance in the box. This works however only, for peri‐
28 odic boundaries in all 3 dimensions. The -norm option (area-) normal‐
29 izes the histograms.
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32 Options to specify input files:
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34 -f [<.xtc/.trr/…>] (traj.xtc)
35 Trajectory: xtc trr cpt gro g96 pdb tng
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37 -n [<.ndx>] (index.ndx)
38 Index file
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40 Options to specify output files:
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42 -ot [<.xvg>] (rkappa.xvg) (Optional)
43 xvgr/xmgr file
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45 -oe [<.xvg>] (insteff.xvg) (Optional)
46 xvgr/xmgr file
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48 -o [<.dat>] (rkappa.dat) (Optional)
49 Generic data file
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51 -rhist [<.xvg>] (rhist.xvg) (Optional)
52 xvgr/xmgr file
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54 -khist [<.xvg>] (khist.xvg) (Optional)
55 xvgr/xmgr file
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57 Other options:
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59 -b <time> (0)
60 Time of first frame to read from trajectory (default unit ps)
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62 -e <time> (0)
63 Time of last frame to read from trajectory (default unit ps)
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65 -tu <enum> (ps)
66 Unit for time values: fs, ps, ns, us, ms, s
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68 -[no]w (no)
69 View output .xvg, .xpm, .eps and .pdb files
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71 -xvg <enum> (xmgrace)
72 xvg plot formatting: xmgrace, xmgr, none
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74 -[no]pbcdist (no)
75 Distance R based on PBC
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77 -[no]norm (no)
78 Normalize histograms
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80 -bins <int> (50)
81 # of histogram bins
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83 -R0 <real> (-1)
84 Foerster radius including kappa^2=2/3 in nm
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87 gmx(1)
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89 More information about GROMACS is available at <‐
90 http://www.gromacs.org/>.
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93 2019, GROMACS development team
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982019.4 Oct 02, 2019 GMX-DYECOUPL(1)