[gmx-users] TYR residue in OPLS-AA

[Chris Neale]

I think that it is worth having a central repository that lists modifications to forcefield files during development -- especially
changes as opposed to simple additions. It's not always a huge deal, but it would be nice if this information was easily available. 
Revision history might be one place for it, but the wiki would also suffice.

This change to OPLSAA TYR charge groups appears to have been made between gromacs 3.3.1 and 3.3.3. 


Based on:
http://www.gromacs.org/pipermail/gmx-users/2006-December/025075.html

Adam Mazur wrote:
>/ Dear All!
/>/ 
/>/ I have noticed an error in TYR residue in OPLS-AA, Gromacs 3.3.1
/>/ Have a look at ffoplsaanr.rtp:
/>/ CG of TYR should be in the same charge group as CB,HB1 and HB2.
/>/ 
/>/ [ TYR ]
/>/  [ atoms ]
/>/      N    opls_238   -0.500     1
/>/      H    opls_241    0.300     1
/>/     CA    opls_224B   0.140     1
/>/     HA    opls_140    0.060     1
/>/     CB    opls_149   -0.005     2
/>/    HB1    opls_140    0.060     2
/>/    HB2    opls_140    0.060     2
/>/     CG    opls_145   -0.115     3 <---
/>/    CD1    opls_145   -0.115     4
/>/    HD1    opls_146    0.115     4
/>/ ....
/>/ 
/>/ Maybe,  it's not of great importance, but it would be nice to have a correct 
/>/ version.
/>/ 
/Thanks for pointing that out. As long as one is using PME there is no 
difference, but when using cut-offs there might be an issue.

-- 
David.