<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;"><DIV>Respectable Justin/Mark</DIV>
<DIV>For the study of diffusion of oxygen in water, I tried to search the itp file for oxygen molecule but could not find. Therefore, I have tried to make it myself.</DIV>
<DIV> </DIV>
<DIV>Please tell me whether it is fine.</DIV>
<DIV> </DIV><FONT size=2>
<DIV>[ moleculetype ]</DIV>
<DIV>; molname nrexcl</DIV>
<DIV>OMOL 1 ; as there are two atoms in an oxygen molecule</DIV>
<DIV> </DIV>
<DIV>[ atoms ]</DIV>
<DIV>; nr type resnr residue atom cgnr charge mass</DIV>
<DIV>1 OB 1 OMOL OB1 0 0</DIV>
<DIV>2 OB 1 OMOL OB2 0 0</DIV>
<DIV> </DIV>
<DIV>[ bonds ]</DIV>
<DIV>;ai aj funct c0 c1</DIV>
<DIV>1 2 1 1.244000000e-01 3.472866e+05; taken from Gaussian calculation. </DIV>
<DIV> </DIV>
<DIV>[ pairtypes ] ; for non bonded interaction within each molecule with exclusion</DIV>
<DIV>; i j func c6 c12</DIV>
<DIV>OB OB 1 0.008261659 1.7392E-05;parameters from CRC Hand book of physics and chemistry.</DIV>
<DIV> </DIV>
<DIV>;[ pairs ] no need of 1-4 interaction pairs as there are only two atoms.</DIV>
<DIV>; ai aj funct c6 c12</DIV>
<DIV>; 1 2 1 0.008261659 1.7392E-05;from CRC0</DIV>
<DIV> </DIV>
<DIV>[ nonbond_params ]</DIV>
<DIV>; OB OW 1 0.004679059 6.853E-06; using L-B rule </DIV>
<DIV>; OB H 1 0 0; taken from OW-H</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>[ exclusions ]</DIV>
<DIV>1 2 ; because the nrexc1 is 1.</DIV>
<DIV> </DIV>
<DIV>Please tell me where I am wrong.</DIV>
<DIV>for nonbonded interaction </DIV></FONT></td></tr></table><br>