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Hi all,<br>
<br>
I just realized the the format of defining the <b>atom-name</b> in
[atomtypes] section in ffnonbond.ipt in different forcefields are
different. such as<br>
1. oplsaa.ff/<br>
[ atomtypes ]<br>
<b>; name bond_type</b> mass charge ptype sigma
epsilon<br>
<b> opls_001 C 6 </b> 12.01100 0.500 A
3.75000e-01 4.39320e-01 ; SIG<br>
<br>
2. charmm27.ff (similar as amber99.ff and gromos53a6.ff)<br>
[ atomtypes ]<br>
<b>;name at.num </b> mass charge ptype sigma epsilon<br>
<b>C 6 </b> 12.01100 0.51 A 0.356359487256
0.46024<br>
<br>
3. Martini FF<br>
[ atomtypes ]<br>
<b>; name </b>mass charge ptype c6 c12<br>
<b>P5</b> 72.0 0.000 A 0.0 0.0<br>
<br>
I wonder how gromacs deals with these difference smartly? And if I want
to write my force field files, what should I pay attention to this
difference?<br>
<br>
best wishes,<br>
Baofu Qiao<br>
<br>
<br>
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