Dear Bruce D.Ray...<br><br>I had used the TPO parameters as u gave in previous posts.<br><br><br><span>[
<b style="color: black; background-color: rgb(255, 255, 102);">TPO</b> ]</span><br><span> [
atoms ]</span><br><span>
N <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_238 -0.500 1</span><br><span>
H <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_241 0.300 1</span><br><span>
CA <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_224B 0.140 1</span><br><span>
HA <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_140 0.060 1</span><br><span>
CB <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_158 0.205 2</span><br><span>
HB <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_140 0.060 2</span><br><span>
OG1 <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_447 -0.700 2</span><br><span>
P <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_445 1.795 3</span><br><span>
O1P <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_446 -1.120 3</span><br><span>
O2P <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_446 -1.120 3</span><br><span>
O3P <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_446 -1.120 3</span><br><span>
CG2 <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_135 -0.180 4</span><br><span>
HG21 <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_140 0.060 4</span><br><span>
HG22 <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_140 0.060 4</span><br><span>
HG23 <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_140 0.060 4</span><br><span>
C <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_235 0.500 5</span><br><span>
O <b style="color: black; background-color: rgb(255, 255, 102);">opls</b>_236 -0.500 5</span><br><span> [
bonds ]</span><br><span>
N H</span><br><span>
N CA</span><br><span>
CA HA</span><br><span>
CA CB</span><br><span>
CA C</span><br><span>
CB HB</span><br><span>
CB OG1</span><br><span>
CB CG2</span><br><span>
OG1 P</span><br><span>
O1P P</span><br><span>
O2P P</span><br><span>
O3P P</span><br><span>
CG2 HG21</span><br><span>
CG2 HG22</span><br><span>
CG2 HG23</span><br><span>
C O</span><br><span>
-C N</span><br><span> [
dihedrals ] ; override some of the typebased dihedrals</span><br><span>
N CA CB OG1 dih_SER_THR_chi1_N_C_C_O</span><br><span>
C CA CB OG1 dih_SER_THR_chi1_CO_C_C_O</span><br><span>
CA CB OG1 HG1 dih_SER_THR_chi2_C_C_OH_HO</span><br><span> [
impropers ]</span><br><span>
-C CA N H improper_Z_N_X_Y </span><br><span>
CA +N C O improper_O_C_X_Y </span><br clear="all"><br><br>And i added Ryckaert-Belleman dihedrals in ffoplsaabon.itp file basing on the errors got after i run pdb2gmx command.<br><br>And i had left the 6 coefficients (c0 to c5) as 0.0000 because i dunno how to derive those values.<br>
<br>So please help me how to fill those values. I had gone through the RB dihedrals main article but im not clear.<br><br>Just give me sugggestions to derive those values and if u have those values it would me much more easier for me....:-)<br>
<br>Thank you in advance<br>sumanth<br><br><br>-- <br><b style="font-family: courier new,monospace;">SUMANTH KUMAR.M</b><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;"></span><br>