# Cut-off scheme - TraPPE-UA

**URL:** <https://gromacs.bioexcel.eu/t/cut-off-scheme-trappe-ua/3858>\
**Category:** User discussions\
**Tags:** mdp-parameters\
**Created:** [March 18, 2022, 9:16am UTC](https://gromacs.bioexcel.eu/t/cut-off-scheme-trappe-ua/3858 "2022-03-18T09:16:30Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![nsigal](https://avatars.discourse-cdn.com/v4/letter/n/258eb7/32.png) [@nsigal](https://gromacs.bioexcel.eu/u/nsigal)\
**Post date:** [March 18, 2022, 9:16am UTC](https://gromacs.bioexcel.eu/t/cut-off-scheme-trappe-ua/3858/1 "2022-03-18T09:16:30Z")

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GROMACS version:  
GROMACS modification: Yes/No  
Hi.  
I want to implement TraPPE-UA in gromacs.  
So, I want to truncate vdw interactions at rvdw=1.2 nm and then use only tail corrections without shifting the potential. Should I use the mdp options displayed below?

cutoff-scheme = Verlet  
verlet-buffer-tolerance = -1  
rlist = 1.4 ; cutoff distance for long range neighbor list

; Options for vdW  
vdwtype = cut-off ; method for van der Waals  
rvdw = 1.2 ; cutoff (nm)  
vdw-modifier = None  
DispCorr = EnerPres

If I set “vdw-modifier = None”, does it take into account rvdw? Or are the interactions calculated for all pairs in the neighbor list?  
Thank you in advance.