# Understanding energy minimization working and acceptable scores

**URL:** <https://gromacs.bioexcel.eu/t/understanding-energy-minimization-working-and-acceptable-scores/194>\
**Category:** User discussions\
**Created:** [May 27, 2020, 4:59am UTC](https://gromacs.bioexcel.eu/t/understanding-energy-minimization-working-and-acceptable-scores/194 "2020-05-27T04:59:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![rahul85](https://avatars.discourse-cdn.com/v4/letter/r/91b2a8/32.png) [@rahul85](https://gromacs.bioexcel.eu/u/rahul85)\
**Post date:** [May 27, 2020, 4:59am UTC](https://gromacs.bioexcel.eu/t/understanding-energy-minimization-working-and-acceptable-scores/194/1 "2020-05-27T04:59:15Z")

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GROMACS version:  
GROMACS modification: Yes/No  
I got the following  
tatistics over 2636 steps [0.0000 through 2635.0000 ps], 1 data sets  
All statistics are over 2087 points (frames)

## Energy Average Err.Est. RMSD Tot-Drift

Potential 7.15491e+07 7.7e+07 3.42742e+09 -4.59299e+08 (kJ/mol)

Is this value acceptable and can I proceed for further equilibration step. I am new to gromac I earlier run tutorial lysozyme in water and the energy minimization average was negative score. But here I use modelled protein for MD and I got positive average as indicated above.

Kindly guide me.

The protein has 11482 atoms  
solvent molecules 94698  
qtot -19

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**Author:** ![cblau](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/cblau/32/5_2.png) [@cblau](https://gromacs.bioexcel.eu/u/cblau)\
**Post date:** [May 27, 2020, 7:09am UTC](https://gromacs.bioexcel.eu/t/understanding-energy-minimization-working-and-acceptable-scores/194/2 "2020-05-27T07:09:34Z")

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Hi Rhaul,

The absolute value of the potential energy is not very meaningful, I suggest you have a look at the change of the potential energy.

If you plot the energy values during your energy minimisation, you would expect a strong drop in energy from the be beginning and then some curve that levels off. That is usually an indication that things went right.

I notice, that you have a large negative charge in your system. Unless you have a very strong reason for this, I suggest you add ions to balance the charges, just as in the lyzosyme tutorial.