# Energy minimization converged to machine precision

**URL:** https://gromacs.bioexcel.eu/t/energy-minimization-converged-to-machine-precision/295
**Category:** User discussions
**Created:** [June 12, 2020, 5:18pm UTC](https://gromacs.bioexcel.eu/t/energy-minimization-converged-to-machine-precision/295 "2020-06-12T17:18:08Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![sadaf](https://avatars.discourse-cdn.com/v4/letter/s/77aa72/32.png) [@sadaf](https://gromacs.bioexcel.eu/u/sadaf)
#### Post date: [June 12, 2020, 5:18pm UTC](https://gromacs.bioexcel.eu/t/energy-minimization-converged-to-machine-precision/295/1 "2020-06-12T17:18:08Z")

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GROMACS version:2020  
GROMACS modification: Yes/No yes  
Here post your question  
Dear Gromacs users  
I am simulating protein-ligand complex and during energy, minimization get following message:-  
Steepest Descents converged to machine precision in 15664 steps,  
but did not reach the requested Fmax \< 10.  
Potential Energy = -2.3425568e+06  
Maximum force = 7.6311267e+02 on atom 2815  
Norm of force = 3.2258615e+00

I tried to do energy minimization in 3 steps as well for which MDP files are attached but still, I am getting the same message. I have read many questions regarding it which shows that either I have bad topology or residue clashes. How should I remove these? I looked the topology seems fine to me I don’t know if it has a problem how can I figure out that?  
Any suggestions will really help me to sort this problem.  
Thanks.  
Sadaf  
[em1.mdp](https://gromacs.bioexcel.eu/uploads/short-url/iydDGOg9ZFuK7vSjGwM1tMUvyPH.mdp) (1.2 KB) [em3.mdp](https://gromacs.bioexcel.eu/uploads/short-url/89ezhvHJzcbFjIELURLFq0YiNxC.mdp) (1.2 KB) [em2.mdp](https://gromacs.bioexcel.eu/uploads/short-url/eleUgQkjxHuRT9vLUvMXc3AGjLV.mdp) (1.2 KB)

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<div class="post-metadata">

### Author: ![jalemkul](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/jalemkul/32/18_2.png) [@jalemkul](https://gromacs.bioexcel.eu/u/jalemkul)
#### Post date: [June 12, 2020, 6:39pm UTC](https://gromacs.bioexcel.eu/t/energy-minimization-converged-to-machine-precision/295/2 "2020-06-12T18:39:50Z")

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> [@sadaf](#):
>
> I have read many questions regarding it which shows that either I have bad topology or residue clashes.

This is only true if Fmax is large. Yours is perfectly reasonable.