<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div id="yiv718855914"><div style="color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: times new roman,new york,times,serif; font-size: 12pt;"><div>Dear GROMACS users, <br></div><div><br></div><div>
I am interested in simulating a DPPC membrane with CHARMM 36 force
field in GROMACS. The charmm36.ff_4.5.4.tgz was downloaded by the
following web page: <a rel="nofollow" target="_blank" href="http://www.gromacs.org/Downloads/User_contributions/Force_fields">http://www.gromacs.org/Downloads/User_contributions/Force_fields</a>.
When the membrane is simulated in NPz(A=0.64nm^2)T ensemble all goes
fine but if I turned to NPT ensemble (P=1bar in z direction and 1bar
for the lateral pressure) the area per lipid reduces significantly. My
question is whether the CHARMM36 force field can be employed with the
NPT ensemble?<br></div><div><br></div><div>Best regards <br></div><div><br></div><div>Giovanni<br></div></div></div> </div></body></html>