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Of my first mail, only the attachment was printed in the mailing
list. I am sorry for the inconvenience. The attachment can be sent
by request.<br>
<br>
----------<br>
<br>
Hi all,<br>
<br>
Recently, I posted a problem concerning the usage of polarizable ff
in conjunction with free energy calculation. Sadly I got no answer,
but after some research, I hope I have isolated the problem.<br>
<br>
Using a polarizable ff without free energy makes no problems. As
soon as free energy is turned on, Gromacs gives the error:<br>
<br>
<i>Program mdrun_d, VERSION 4.5.5<br>
Source code file: [...]/src/gromacs-4.5.5/src/mdlib/shellfc.c,
line: 365<br>
<br>
Fatal error:<br>
polarize can not be used with qA != qB</i><br>
<br>
This error occurs, even if the atom and the shell particle have the
same charge or are unaltered by the free energy option, e.g.
lambda=0.0 and multiplication with (1-lambda). Because of this, I
guess there is a problem with different charge variables being
single and double precision due to multiplication with lambda.<br>
<br>
The error occurs in this segment of shellfc.c:<br>
<small><big><br>
case F_POLARIZATION:<br>
if (qS != atom[aS].qB)<br>
gmx_fatal(FARGS,"polarize can not be used with qA !=
qB");</big><br>
</small><br>
If anybody knows, how to correct this, I would be very grateful.<br>
Moreover I'm wondering about the physical meaning of the
if-statement. <br>
<br>
Best<br>
Tom<br>
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