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<DIV>Dear Dr. David:</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>><I> Dear Gmxers:<BR></I>><I> <BR></I>><I> Is it possible to
apply a gradient electric field in GMX, which is a <BR></I>><I> function of
space? For example, field strength<BR></I>><I> in the left side of simulation
box is set to zero, which gradually <BR></I>><I> changes to 1 V/nm in the
right edge of box.<BR></I>><I> <BR></I>><I> If yes, how to compile
the source code? Thanks.<BR></I></DIV>
<DIV>> You can do periodic fields. Your version would have a discontinuous
<BR>> field at the box edge. Is that really what you want?<BR></DIV>
<DIV>Sorry, I forget the stuff of PBC. Take another example, field strength
increases from 0 V/nm in the </DIV>
<DIV>left side of box to 1 V/nm in the middle part of box, and then decreases to
0V/nm in the right edge. How</DIV>
<DIV>to realize it?</DIV>
<DIV> </DIV>
<DIV>What is your mean of periodic fields? As described in source code, we can
definie an electric field, which is</DIV>
<DIV>varied as time. But at any specific time, field strength in the whole
system should be the same, right?</DIV>
<DIV> </DIV>
<DIV>What I want to get is electric field is not uniform at any time, which is
different at different position in the system.</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV><I></I> </DIV>
<DIV>Thanks and regards,</DIV>
<DIV> </DIV>
<DIV>Xie YH</DIV>
<DIV>Hong Kong University</DIV></BODY></HTML>