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<p>Hello</p>
<p>there is a separate residue for charged GLN (QLN) in the OPLS-forcefield file aminoacids.rtp.</p>
<p>This residue uses the preprocessor define "<span>dih_GLN_chi4_C_C_O_H</span>" for a dihedral parameter set.</p>
<p>However, this macro is not defined anywhere (esp. not in ffbonded.itp with all the others).</p>
<p>The reason why grompp does not complain, is because the function push_bond() uses sscanf</p>
<p><span> nread = sscanf(line,format,&cc[0],</span>.....</p>
<p>expecting double values. When strings are read instead, the variable nread is zero, and grompp assumes</p>
<p>default values for this dihedral.</p>
<p>If I'm correct, we should either delete the non-existing macro, or have to add values for this dihedral.</p>
<p>Thank you for your time,</p>
<p>regards Martin<br>
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