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<DIV><FONT face=Arial size=2><SPAN class=305183313-23112006>Hi, Mark, thanks for
your reply.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=305183313-23112006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=305183313-23112006>After some efforts I
have been successful to insert potassium using ff oplsaa. But it seems that ff
g43a1 actually can not recognize K or K+. It doesnt matter, anyway I can select
ff oplsaa.</SPAN></FONT></DIV>
<DIV> </DIV>
<DIV align=left>
<DIV align=left><FONT face="Times New Roman" size=4>Zhongqiao Hu</FONT></DIV>
<DIV align=left><FONT face="Times New Roman"></FONT> </DIV>
<DIV align=left><FONT face="Times New Roman">Lab E5-04-27</FONT></DIV>
<DIV align=left>
<DIV align=left><FONT face="Times New Roman">Tel: 65161946(O)</FONT></DIV></DIV>
<DIV align=left><FONT face="Times New Roman">Department of Chemical and
Biomolecular Engineering</FONT></DIV>
<DIV align=left><FONT face="Times New Roman">National University of
Singapore</FONT></DIV>
<DIV align=left><FONT face="Times New Roman">117576, Singapore</FONT></DIV>
<DIV align=left><FONT face="Times New Roman"></FONT> </DIV></DIV>
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