<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div dir="ltr">Dear Justin<br>I appreciate for your reply.I used -maxwarn option because grompp gave me:<br>WARNING 1 [file ffbonded.itp, line 2705]:<br> Overriding Bond parameters.<br><br> old: 0.151 292880 0.151 292880 <br> new: C C 1 0.1418 478900<br>I guess I am not using improper in the topology file.my cnt.top file looks like:<br>; Include forcefield parameters<br>#include "./oplsaa.ff/forcefield.itp"<br><br>[ moleculetype ]<br>; Name nrexcl<br>CNT 3<br><br>[ atoms ]<br>; nr type resnr residue atom cgnr
charge mass typeB chargeB massB<br> 1 opls_995 1 UNK C 1 0 12.011 ; qtot 0<br> 2 opls_995 1 UNK C 2 0 12.011 ; qtot 0<br> 3 opls_996 1 UNK C 3 0 12.011 ; qtot
0<br> ......<br>[ bonds ]<br>; ai aj funct c0 c1 c2 c3<br> 1 2 1 1.420000e-01 4.789000e+05 1.420000e-01 4.789000e+05 <br> 1 73 1 1.420000e-01 4.789000e+05 1.420000e-01 4.789000e+05 <br> 2 4 1 1.420000e-01 4.789000e+05 1.420000e-01 4.789000e+05 <br>.....<br><br>[ pairs ]<br>; ai aj funct
c0 c1 c2 c3<br> 1 3 1 <br> 1 5 1 <br> 1 71 1<br>......<br><br>[ angles ]<br>; ai aj ak funct c0 c1 c2 c3<br> 2 1 73 1 1.180000e+02 5.622000e+02 1.180000e+02
5.622000e+02 <br> 1 2 4 1 1.190000e+02 5.622000e+02 1.190000e+02 5.622000e+02 <br> 4 3 9 1 1.200000e+02 5.622000e+02 1.200000e+02 5.622000e+02 <br>........<br><br>[ dihedrals ]<br>; ai aj ak al funct c0 c1 c2 c3 c4 c5<br> 73
1 2 4 3 1.910000e+02 5.000000e+00 3.000000e+00 1.910000e+02 5.000000e+00 3.000000e+00 <br> 2 1 73 72 3 2.520000e+02 5.000000e+00 3.000000e+00 2.520000e+02 5.000000e+00 3.000000e+00 <br> 1 2 4 3 3 2.240000e+02 5.000000e+00 3.000000e+00 2.240000e+02 5.000000e+00 3.000000e+00 <br> ........</div></div></body></html>