<div dir="ltr"><div>Dear Gromacs Users,</div><div><br></div><div>I am trying to
calculate the surface tension of bulk water. I am using TIP4P/2005 water
model consisting of 851 water molecules. The box dimensions are <b>3.71233 3.71233 1.85616.</b></div><div>Following are the parameters for the mdp file which I am using:</div><div><br></div><div>; OPTIONS FOR WEAK COUPLING ALGORITHMS<br>; Temperature coupling<br>;Tcoupl = no<br>Tcoupl = nose-hoover<br>tau_t = 2.0<br>ref_t = 308<br>tc-grps = system<br><br>;Pcoupl = no<br><br>Pcoupl = Berendsen<br>tau_p = 2.0<br>pcoupltype = isotropic<br>ref_p = 1<br>compressibility = 5e-5</div><div><br></div><div>I am using <b>#Surf*SurfTen</b>
option in the g_energy command in GROMACS-4.6.5. I have calculated
surface tension for 70 ns NPT run. Following is the output which I am
getting:</div><div><br></div><div>Statistics over 35000001 steps [ 0.0000 through 70000.0000 ps ], 1 data sets<br>All statistics are over 350001 points<br><br>Energy Average Err.Est. RMSD Tot-Drift<br>-------------------------------------------------------------------------------<br>#Surf*SurfTen -3.53622 2.6 1336.67 0.561131 (bar nm)</div><div><br></div><div><br></div><div>The value for surface tension of bulk water at 308 K is 70.38 dyn/cm. <br></div><div><br></div><div><br></div><div>Kindly tell me whether I am giving some wrong input parameters? <br></div><div><br></div><div><br></div><div>Regards,</div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><b>Abhinav Srivastava</b><br><font size="1"><i>Research Scholar</i><br></font></div><div><font size="1">Indian Institute of Technology, Jodhpur<br></font></div><div><font size="1">Rajasthan</font><br></div></div></div></div>