CCL: Imidazoliums

 Sent to CCL by: Chris Moth [chris.moth^^vanderbilt.edu]
You might take a peek at the "HIP" (protonated histidine) residue in the AMBER force field for some inspiration/validation. 
 See page 5190 of
 Cornell et. al, J. Am. Chem. SOC. 1995, 117, 5179-5197
Though, imidazolium should likely be parameterized in the context of your particular MD force field. 
 John Daily john.daily],[colorado.edu wrote:
 
 Sent to CCL by: John Daily [john.daily,colorado.edu]
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 Folks,
Does anyone have experience with charged imidazoliums? I am doing molecular dynamic calculations on small droplets of ionic liquids. Obviously as the size of the drops increases, using quantum methods gets too expensive. However, I have not been able to find force field parameters for N+ CCNC five member rings. In particular bond stretching, angle bending and torsional parameters. 
 Any suggestions appreciated.
 John
 University of Colorado at Boulder
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 ">Folks,<BR><DIV></DIV><DIV><BR =
 class=3D"khtml-block-placeholder"></DIV><DIV>Does
 anyone have experience =
 with charged imidazoliums? I am doing molecular dynamic calculations on =
 small droplets of ionic liquids. Obviously as the size of the drops =
 increases, using quantum methods gets too expensive. However, I have not =
 been able to find force field parameters for N+ CCNC five member rings. =
 In particular bond stretching, angle bending and torsional =
 parameters.=A0</DIV><DIV><BR =
 class=3D"khtml-block-placeholder"></DIV><DIV>Any
 suggestions =
 appreciated.</DIV><DIV><BR =
 class=3D"khtml-block-placeholder"></DIV><DIV>John</DIV><DIV><P
 =
 style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><FONT
 face=3D"Helvetica" =
 size=3D"3" style=3D"font: 12.0px Helvetica">University of
 Colorado at =
 Boulder</FONT></P> </DIV><BR =
 class=3D"khtml-block-placeholder"></BODY></HTML>=
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