[gmx-users] Coordination number

[Venkat Reddy]

Dear Gromacs Users,

I have a query about the g_rdf utility. I have two different systems of
water with Ionic Liquid 1 and Ionic Liquid 2. When I plot the rdf using

g_rdf -f x_gro.pdb -s x.pdb -n rdf.ndx -o rdf1.xvg/rdf2.xvg -cn
rdf1_cn.xvg/rdf2_cn.xvg -rdf res_com

where rdf1/rdf2 is for water distribution around Ionic liquid 1/2,

the rdf1.xvg clearly shows a higher first peak g(r) than the rdf2.xvg. Both
also have minima at the same distance. However, the coordination number at
first minima from rdf1_cn.xvg is lesser than the same from rd2_cn.xvg. How
is this possible? If the peak is larger, the integration of it should give
a higher value right?

Please help.


-- 
With Best Wishes
Venkat Reddy Chirasani
PhD student
Laboratory of Computational Biophysics
Department of Biotechnology
IIT Madras
Chennai
INDIA-600036