# Adding NH3+ in both terminal in amber force field

**URL:** <https://gromacs.bioexcel.eu/t/adding-nh3-in-both-terminal-in-amber-force-field/9273>\
**Category:** User discussions\
**Created:** [May 31, 2024, 8:03pm UTC](https://gromacs.bioexcel.eu/t/adding-nh3-in-both-terminal-in-amber-force-field/9273 "2024-05-31T20:03:20Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![alexmathew](https://avatars.discourse-cdn.com/v4/letter/a/f4b2a3/32.png) [@alexmathew](https://gromacs.bioexcel.eu/u/alexmathew)\
**Post date:** [May 31, 2024, 8:03pm UTC](https://gromacs.bioexcel.eu/t/adding-nh3-in-both-terminal-in-amber-force-field/9273/1 "2024-05-31T20:03:20Z")

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GROMACS version:  
GROMACS modification: Yes/No  
Here post your question

someone can tell me how i can add NH3+ terminal on both c and n termini in ambersb force field.