# Inconsistent shifts over periodic boundaries

**URL:** <https://gromacs.bioexcel.eu/t/inconsistent-shifts-over-periodic-boundaries/6920>\
**Category:** User discussions\
**Tags:** mdrun\
**Created:** [July 29, 2023, 9:49am UTC](https://gromacs.bioexcel.eu/t/inconsistent-shifts-over-periodic-boundaries/6920 "2023-07-29T09:49:52Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kesavanekambaram](https://avatars.discourse-cdn.com/v4/letter/k/67e7ee/32.png) [@kesavanekambaram](https://gromacs.bioexcel.eu/u/kesavanekambaram)\
**Post date:** [July 29, 2023, 9:49am UTC](https://gromacs.bioexcel.eu/t/inconsistent-shifts-over-periodic-boundaries/6920/1 "2023-07-29T09:49:52Z")

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GROMACS version:2022-beta1  
GROMACS modification: No  
Hi Everyone,  
I am trying to run a Martini system built with Martini 22 forcefield for my protein and while performing the minimization, I am getting an fatal error.  
Fatal error:  
There are inconsistent shifts over periodic boundaries in a molecule type  
consisting of 272 atoms. The longest distance involved in such interactions is  
8.998 nm which is close to half the box length. Eithe you have excessively  
large distances between atoms in bonded interactions or your system is  
exploding.

I have given the correct periodic boundary condition for the system. But still, ended up with this error. Could anyone help me out with this ?

With regards,  
Kesavan

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**Author:** ![hess](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/hess/32/416_2.png) [@hess](https://gromacs.bioexcel.eu/u/hess)\
**Post date:** [July 31, 2023, 8:23am UTC](https://gromacs.bioexcel.eu/t/inconsistent-shifts-over-periodic-boundaries/6920/2 "2023-07-31T08:23:12Z")

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Could it be that during system preparation you increased you box size with this molecule being broken over the periodic boundary?