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Hi all,<br>
<br>
I want to test the g_dipoles tool and made a 20 ns simulation with
SPC/E water. Sadly the result for the dielectric constant
(e_sim=109.713) looks very different from experimental (e_exp=78)
and reported values for SPCE (e_paper=70). I put the command line
and the output below.<br>
<pre wrap="">Gromacs 4.5.3, SPC/E water, 20ns, NPT, 300K, 1bar
g_dipoles -corr total -c dipoles -f md_20ns.xtc -s md_20ns.tpr -b 0 -e 20000
#==========================================
Using 5 as mu_max and -1 as the dipole moment.
WARNING: EpsilonRF = 0.0, this really means EpsilonRF = infinity
Selected 0: 'System'
There are 1024 molecules in the selection
Using Volume from topology: 30.2049 nm<sup class="moz-txt-sup">3</sup>
Average volume over run is 30.2103
t0 0, t 20000, teller 10001
Dipole moment (Debye)
---------------------
Average = 2.4883 Std. Dev. = 0.1342 Error = 0.0000
The following averages for the complete trajectory have been calculated:
Total < M_x > = 1.45986 Debye
Total < M_y > = 5.71202 Debye
Total < M_z > = 3.39196 Debye
Total < M_x<sup class="moz-txt-sup">2</sup> > = 10964.8 Debye<sup class="moz-txt-sup">2</sup>
Total < M_y<sup class="moz-txt-sup">2</sup> > = 10794.4 Debye<sup class="moz-txt-sup">2</sup>
Total < M_z<sup class="moz-txt-sup">2</sup> > = 10762.4 Debye<sup class="moz-txt-sup">2</sup>
Total < <code class="moz-txt-verticalline"><span class="moz-txt-tag">|</span>M<span class="moz-txt-tag">|</span></code>^2 > = 32521.6 Debye<sup class="moz-txt-sup">2</sup>
Total |< M >|^2 = 46.2638 Debye<sup class="moz-txt-sup">2</sup>
< <code class="moz-txt-verticalline"><span class="moz-txt-tag">|</span>M<span class="moz-txt-tag">|</span></code>^2 > - |< M >|^2 = 32475.4 Debye<sup class="moz-txt-sup">2</sup>
Finite system Kirkwood g factor G_k = 5.12208
Infinite system Kirkwood g factor g_k = 3.43028
Epsilon = 109.713
#==========================================
I would be really grateful if anybody could point me to my error. I
attached my .mdp file in case the error lies there.
Best regards
Tom
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