# I am getting this warning when I am performing Energy minimization

**URL:** <https://gromacs.bioexcel.eu/t/i-am-getting-this-warning-when-i-am-performing-energy-minimization/8821>\
**Category:** User discussions\
**Created:** [April 8, 2024, 11:14am UTC](https://gromacs.bioexcel.eu/t/i-am-getting-this-warning-when-i-am-performing-energy-minimization/8821 "2024-04-08T11:14:09Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![sharaddzz](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/sharaddzz/32/3158_2.png) [@sharaddzz](https://gromacs.bioexcel.eu/u/sharaddzz)\
**Post date:** [April 8, 2024, 11:14am UTC](https://gromacs.bioexcel.eu/t/i-am-getting-this-warning-when-i-am-performing-energy-minimization/8821/1 "2024-04-08T11:14:10Z")

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NOTE 3 [file topol.top, line 44]:  
System has non-zero total charge: 0.179030  
Total charge should normally be an integer. See  
[Floating point arithmetic — GROMACS webpage https://www.gromacs.org documentation](http://www.gromacs.org/Documentation/Floating_Point_Arithmetic)  
for discussion on how close it should be to an integer.

WARNING 1 [file topol.top, line 44]:  
You are using Ewald electrostatics in a system with net charge. This can  
lead to severe artifacts, such as ions moving into regions with low  
dielectric, due to the uniform background charge. We suggest to  
neutralize your system with counter ions, possibly in combination with a  
physiological salt concentration.

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**Author:** ![MagnusL](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/magnusl/32/2380_2.png) [@MagnusL](https://gromacs.bioexcel.eu/u/MagnusL)\
**Post date:** [April 8, 2024, 11:33am UTC](https://gromacs.bioexcel.eu/t/i-am-getting-this-warning-when-i-am-performing-energy-minimization/8821/2 "2024-04-08T11:33:29Z")

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As the note and warning say, you have a non-integer total charge in the system. That indicates that something is not correctly setup. The first thing you should do is to look through your topology. There must be at least one molecule with non-integer charges.

But without more information about how you generated your topology, it is difficult to help.
