# 5/1    0.93624                         WARNING: Particle 182006 had a negative distance to a lattice boundary. d =           -4.00163

**URL:** https://openmc.discourse.group/t/5-1-0-93624-warning-particle-182006-had-a-negative-distance-to-a-lattice-boundary-d-4-00163/217
**Category:** User Support
**Created:** [June 9, 2016, 2:46am UTC](https://openmc.discourse.group/t/5-1-0-93624-warning-particle-182006-had-a-negative-distance-to-a-lattice-boundary-d-4-00163/217 "2016-06-09T02:46:58Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Shawn\_H\_Wachter](https://avatars.discourse-cdn.com/v4/letter/s/cdc98d/32.png) [@Shawn\_H\_Wachter](https://openmc.discourse.group/u/Shawn_H_Wachter)
#### Post date: [June 9, 2016, 2:46am UTC](https://openmc.discourse.group/t/5-1-0-93624-warning-particle-182006-had-a-negative-distance-to-a-lattice-boundary-d-4-00163/217/1 "2016-06-09T02:46:58Z")

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Am getting the above message. The geometry.xml file is attached. It is a model of the DMSR core.

Any help would be greatly appreciated.

Thanks,

Shawn Wachter

[geometry.xml](https://openmc.discourse.group/uploads/short-url/9IUPCYvq9AXPMsm1PPdiYSAG7ls.xml) (47.4 KB)

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### Author: ![paulromano](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/paulromano/32/486_2.png) [@paulromano](https://openmc.discourse.group/u/paulromano)
#### Post date: [June 29, 2016, 3:56am UTC](https://openmc.discourse.group/t/5-1-0-93624-warning-particle-182006-had-a-negative-distance-to-a-lattice-boundary-d-4-00163/217/2 "2016-06-29T03:56:13Z")

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Shawn – sorry for the delayed response on this. Can you tell us a little more about your run configuration:

What version of OpenMC are you using?  
What cross sections are you using?

When I created a fake materials and settings file and use them along with your geometry.xml to do a quick run, I’m unable to reproduce any geometry error.

Best,  
Paul